Electrical propulsion heat rejection system, power plant, and aircraft

Abstract

The application relates to an electric propulsion heat dissipation system, a power device and an aircraft, and relates to the technical field of the aircraft. The electric propulsion heat dissipation system comprises a propeller, an arm and an electric motor, the arm is fixedly connected to a body structure of the aircraft, the propeller is arranged at an output end of the electric motor, the arm is provided with an assembly space, the electric motor is installed in the assembly space and can drive the propeller to rotate around an axis of the electric motor; a surface of the arm on a side facing the propeller is provided with an inlet, airflow generated when the propeller rotates can at least partially cover the inlet, a surface of the arm on a side away from the propeller is provided with an outlet, the airflow can flow through the electric motor arranged in the assembly space through the inlet, and then enter an external space through the outlet. The electric propulsion heat dissipation system, the power device and the aircraft provided by the application solve the problem that the heat dissipation capacity of the electric propulsion heat dissipation system of the existing aircraft is poor under flight conditions such as hovering or vertical take-off and landing.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of aircraft technology, in particular to an electric propulsion heat dissipation system, a power device and an aircraft. BACKGROUND

[0002] In the field of electric vertical take-off and landing (eVTOL for short) aircraft, the electric propulsion system as the core power component inevitably generates a large amount of heat energy in the process of energy conversion. These heat energy needs to be dissipated efficiently through the cooling system to avoid performance degradation or functional failure caused by abnormal temperature rise of the system. The cooling system usually includes a heat sink, and its heat dissipation mechanism relies on the forced convection heat exchange process between the external airflow and the surface of the heat sink. The design of the airflow flow path directly affects the heat transfer efficiency. If the heat dissipation capacity is insufficient, it may cause the temperature of the key components of the electric motor to exceed the safety threshold, thereby causing the electric control system to be disorderly, the material to age rapidly, and even the structure to fail, which seriously threatens the overall safety of the aircraft.

[0003] The existing heat dissipation scheme mainly cools the electric motor by using the relative airflow generated during the level flight of the aircraft. However, when the aircraft is in a hovering or vertical take-off flight condition, the electric motor needs to output more power to maintain the flight attitude, resulting in a sharp increase in heat generation per unit time. This imbalance between heat dissipation demand and airflow supply makes the electric motor prone to accumulate excessive heat in a short time, causing local overheating. Especially in long-time hovering operation, the continuous lack of heat dissipation capacity may cause the motor to shut down for protection or permanent damage, seriously restricting the practicability and reliability of the aircraft. SUMMARY

[0004] Therefore, it is necessary to provide an electric propulsion heat dissipation system, a power device and an aircraft to solve the problem that the existing aircraft has poor heat dissipation capacity of the electric propulsion heat dissipation system in a hovering or vertical take-off flight condition.

[0005] The electric propulsion heat dissipation system provided by the present application includes a propeller, an arm and an electric motor. The arm is fixedly connected to the body structure of the aircraft. The propeller is arranged at the output end of the electric motor. The arm is provided with an assembly space. The electric motor is installed in the assembly space and can drive the propeller to rotate. The surface of the arm on the side facing the propeller is provided with an inlet. The airflow generated when the propeller rotates can at least partially cover the inlet. The surface of the arm on the side away from the propeller is provided with an outlet. The inlet, the assembly space and the outlet are sequentially communicated.

[0006] In one embodiment, the inlet includes a first inlet and a second inlet. The orthographic projection of the corresponding surface of the arm on the propeller at least partially covers one of the first inlet and the second inlet when the propeller rotates.

[0007] In one of the embodiments, the first inlet is arranged at a front side region of the propeller shaft, and the second inlet is arranged at a rear side region of the propeller shaft.

[0008] In one of the embodiments, the first inlet is provided with a first grille, the first grille comprises a plurality of first flow guide strips arranged side by side, adjacent first flow guide strips are arranged at intervals to form a plurality of first flow guide gaps, and the airflow can pass through the plurality of first flow guide gaps and enter the assembly space respectively; the second inlet is provided with a second grille, the second grille comprises a plurality of second flow guide strips arranged side by side, adjacent second flow guide strips are arranged at intervals to form a plurality of second flow guide gaps, and the airflow can pass through the plurality of second flow guide gaps and enter the assembly space respectively.

[0009] In one of the embodiments, along the direction from the first inlet to the second inlet, the plurality of first flow guide strips are arranged at intervals, and the length of each first flow guide strip tends to increase.

[0010] In one of the embodiments, the first flow guide strip is stopped at the front side region of the first inlet.

[0011] In one of the embodiments, the plane where the first inlet is located is arranged to be inclined relative to the horizontal plane, along the direction from the first inlet to the second inlet, the height of the plane where the first inlet is located tends to gradually increase, and the surface on the side away from the assembly space of the first flow guide strip is arranged to be curved in the form of an arc.

[0012] In one of the embodiments, the blowing direction of the propeller during rotation towards the first inlet is defined as a first preset air outlet direction, and the airflow along the first preset air outlet direction can directly pass through the first flow guide gap and enter the assembly space. The flow direction of the first flow guide gap is the same as the first preset air outlet direction.

[0013] In one of the embodiments, along the direction from the first inlet to the second inlet, the plurality of second flow guide strips are arranged at intervals, and the length of each second flow guide strip is the same.

[0014] In one of the embodiments, the blowing direction of the propeller during rotation towards the second inlet is defined as a second preset air outlet direction, and the airflow along the second preset air outlet direction can directly pass through the second flow guide gap and enter the assembly space.

[0015] In one of the embodiments, the second flow guide gap extends in the form of an arc, the flow direction at the opening of the second flow guide gap close to the propeller is the same as the second preset air outlet direction, and the flow direction at the opening of the second flow guide gap close to the assembly space is arranged vertically downward.

[0016] In one of the embodiments, the plane where the second inlet is located is the same as the shape of the outer contour of the arm.

[0017] In one of the embodiments, the arm is provided with a first flow channel part, the first inlet is communicated with the assembly space through the first flow channel part; along the air inlet direction from the first inlet to the assembly space, the flow area of the first flow channel part shows a trend of increasing; and / or, the arm is provided with a second flow channel part, the second inlet is communicated with the assembly space through the second flow channel part; along the air inlet direction from the second inlet to the assembly space, the flow area of the second flow channel part shows a trend of increasing.

[0018] In one of the embodiments, the third grid is arranged at the outflow port, and the third grid comprises a plurality of third flow guide strips arranged side by side, and the third flow guide strips are arranged at intervals to form third flow guide gaps.

[0019] In one of the embodiments, the third flow guide strips are in the form of slats, and the third flow guide gaps are arranged vertically downward.

[0020] In one of the embodiments, the electric motor includes a power motor, a fan motor, a cooling fan, a radiator and a fan frame, the power motor is used to drive the propeller to rotate, the fan motor is used to drive the cooling fan to rotate, the radiator can cool the power motor through the circulation of the cooling liquid, and the radiator is arranged on the side of the cooling fan away from the power motor; one end of the fan frame is sleeved on the outer circumferential side of the fan motor, and the other end extends toward the direction away from the power motor and is sleeved on the outer circumferential side of the cooling fan; a first part of the external airflow can pass through the fan motor, the cooling fan and the radiator in sequence, a second part of the external airflow can pass through the fan frame, the fan blades of the cooling fan and the radiator in sequence along the axial direction of the power motor, and a third part of the external airflow first passes through the outer circumferential side of the fan frame along the radial direction of the fan frame, and then passes through the fan blades of the cooling fan and the radiator in sequence along the axial direction of the fan frame.

[0021] In one of the embodiments, the fan motor and the power motor have a mounting space communicated with the inflow port, and the fan motor is provided with a cooling channel for passing the external airflow, so that the airflow in the mounting space can pass through the fan motor through the cooling channel and flow toward the inflow port.

[0022] In one of the embodiments, the radiator is at least partially overlapped with the orthographic projection of the corresponding surface of the arm on the outflow port, or the orthographic projection of the radiator on the corresponding surface of the arm is completely covered by the outflow port.

[0023] The application provides a power device, which comprises a power battery and an electric propulsion cooling system according to any one of the above embodiments, the power battery is mounted on the body structure of an aircraft, and the power battery is electrically connected with the electric propulsion cooling system to supply power to the electric propulsion cooling system.

[0024] The application provides a kind of aircraft, the aircraft includes fuselage, wing and the electric propulsion heat dissipation system described in any one of the above embodiments, wing is connected to fuselage, electric propulsion heat dissipation system is installed in one or both of wing and fuselage.

[0025] In one embodiment, the aircraft is configured as an electric vertical take-off and landing aircraft.

[0026] Compared with the prior art, the electric propulsion heat dissipation system, power device and aircraft provided by the application, the electric propulsion heat dissipation system is fixedly connected to the wing or fuselage of the aircraft through the arm, and the electric motor is installed in the arm and drives the propeller to rotate around its axis. During rotation, the propeller sweeps an area that generates airflow, and since the side surface of the arm facing the propeller is provided with an inlet, and the airflow generated by the rotation of the propeller at least partially covers the inlet, the airflow is driven by the rotation of the propeller and guided into the inlet. The incoming airflow then flows through the electric motor in the assembly space and exchanges heat with the heat dissipation components inside the engine, carrying away the heat generated during operation, and finally discharged into the external environment through the outlet on the side surface of the arm away from the propeller. The design of such an airflow path enables the establishment of a heat dissipation cycle during the hovering or vertical take-off stage of the aircraft, avoiding the limitations of relying on natural airflow during flight. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the drawings needed in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0028] Figure 1 Structure diagram of the aircraft provided by an embodiment of the application;

[0029] Figure 2 Partial structure diagram of the electric propulsion heat dissipation system provided by an embodiment of the application Figure 1 ;

[0030] Figure 3 Wind speed diagram corresponding to the blade of the propeller shown in Figure 2 ;

[0031] Figure 4 Partial structure diagram of the electric propulsion heat dissipation system provided by an embodiment of the application Figure 2 ;

[0032] Figure 5 Partial structure diagram of the electric propulsion heat dissipation system provided by an embodiment of the application Figure 3 ;​

[0033] Figure 6 for Figure 5 The sectional view at point AA is shown.

[0034] Figure 7 A schematic diagram of the assembly structure of the second grille and the arm according to an embodiment provided in this application;

[0035] Figure 8 for Figure 7 The sectional view at point BB is shown.

[0036] Figure 9 A schematic diagram of the assembly structure of the first grille and the arm according to an embodiment provided in this application;

[0037] Figure 10 A cross-sectional view of the assembly structure of the first grid and the arm according to an embodiment provided in this application;

[0038] Figure 11 A schematic diagram of the assembly structure of the third grille and the arm according to an embodiment provided in this application;

[0039] Figure 12 A partial structural diagram of an electric propulsion heat dissipation system according to an embodiment of this application. Figure 4 ;

[0040] Figure 13 A partial structural diagram of an electric propulsion heat dissipation system according to an embodiment of this application. Figure 5 ;

[0041] Figure 14 A schematic diagram of the structure of a fan motor according to an embodiment of this application. Figure 1 ;

[0042] Figure 15 A schematic diagram of the structure of a fan motor according to an embodiment of this application. Figure 2 ;

[0043] Figure 16 A schematic diagram of the structure of a fan motor according to another embodiment provided in this application;

[0044] Figure 17 A schematic diagram of the structure of a cooling fan according to an embodiment of this application;

[0045] Figure 18 A schematic diagram of the structure of a cooling fan according to another embodiment of this application;

[0046] Figure 19 A schematic diagram of the structure of a fan frame according to an embodiment provided in this application;

[0047] Figure 20Structure diagram of a guide vane of an embodiment provided in the present application;

[0048] Figure 21 Structure diagram of a guide vane of an embodiment provided in the present application.

[0049] 100, power device; 110, electric propulsion cooling system; 111, electric motor; 1111, power motor; 1112, fan motor; 1201, cooling channel; 1202, axial inlet; 1203, radial inlet; 1204, axial outlet; 1113, radiator; 1114, cooling fan; 1401, center support; 1402, through hole; 1403, fan blade; 1404, wind guard; 1115, fan frame; 1501, guide vane; 1502, inner ring support; 1503, outer ring support; 1504, connecting support; 1505, reinforcing cross bar; 1506, air flow groove; 112, propeller; 113, arm; 1131, assembly space; 1132, inlet; 1133, first inlet; 1134, second inlet; 1135, outlet; 1136, first guide passage part; 1137, second guide passage part; 114, first grid; 1141, first guide strip; 1142, first guide gap; 115, second grid; 1151, second guide strip; 1152, second guide gap; 116, third grid; 1161, third guide strip; 1162, third guide gap; 210, wing; 220, tail; 230, fuselage; 240, tilting rotor; 250, fixed rotor. DETAILED DESCRIPTION

[0050] Please refer to Figures 1-21The application provides a flying vehicle, which is configured as an electric vertical take-off and landing (eVTOL) flying vehicle. The flying vehicle comprises a fuselage 230, wings 210, a tail 220, tilting rotors 240 and fixed rotors 250. The tilting rotors 240 and the fixed rotors 250 are each provided with a power device 100, which is installed on one, two or more of the fuselage 230, the wings 210, the tail 220 and a wing arm 113. The wings 210 are symmetrically arranged on both sides of the fuselage 230. The tail 220 is arranged at the tail of the fuselage 230 and is symmetrically arranged relative to the fuselage 230. The tilting rotors 240 are installed on both sides of the fuselage 230. Part of the tilting rotors 240 are installed on the tail 220, and the other part of the tilting rotors 240 are installed on one or both of the fuselage 230 and the wings 210. The tilting rotors 240 can be directly installed on the wings 210 or installed on the wings 210 or the fuselage 230 through the wing arm 113. The fixed rotors 250 are installed on both sides of the fuselage 230 and connected to one or both of the fuselage 230 and the wings 210. The fixed rotors 250 are located outside the tilting rotors 240. The fixed rotors 250 can be in any suitable form. The fixed rotors 250 can be installed on the fuselage 230 or the wings 210 in any suitable position. For example, the fixed rotors 250 can be installed on the wings 210 or the fuselage 230 through the wing arm 113.

[0051] The power device 100 provided by the application is a device for providing power for the flying vehicle. The power device is installed on the fixed rotors 250 and comprises an electric propulsion cooling system 110, a power battery (not shown) and a power distribution system (not shown). The power battery is installed on one, two or three of the fuselage 230, the wings 210 and the wing arm 113. The power battery is electrically connected to the electric propulsion cooling system to supply power to the electric propulsion cooling system.

[0052] In the current eVTOL electric propulsion system, when the flying vehicle is in the hovering or vertical take-off stage, it is difficult to effectively introduce external airflow into the cooling system, and the radiator is difficult to timely remove the heat generated by the electric motor due to the lack of forced convection. The heat load of the electric motor increases significantly when the electric motor operates at high power, which reduces the heat dissipation efficiency and affects the thermal management performance and operation stability of the electric propulsion system.

[0053] For example, during the process of vertical take-off and landing or hovering of the aircraft, the output power of the electric motor of the fixed rotor installed on the arm is increased to meet the lift demand. The radiator surface of the fixed rotor is difficult to form sufficient airflow heat exchange conditions, and the heat continues to accumulate inside the electric motor. Specifically, the airflow stagnation phenomenon in the assembly space leads to rapid temperature rise of the radiator substrate, thereby causing the insulation material of the electric motor to face the risk of thermal stress damage, and the heat exchange efficiency of the cooling medium is reduced, eventually resulting in frequent triggering of the system thermal protection mechanism.

[0054] If the above problems are not solved, the continuous overheating state of the electric motor will trigger a chain of failures such as accelerated aging of the insulation layer and failure of the power module, and the risk of thermal runaway is significantly increased, which may cause the electric propulsion system to completely stop, thereby threatening the flight control ability of the aircraft and the safety of personnel. Further, the universality of the problem in the hovering and vertical take-off and landing conditions of the aircraft makes it difficult for the existing heat dissipation design to meet the safe operation requirements of the full flight envelope.

[0055] To this end, as shown in the accompanying drawings, Figures 2-13 The electric propulsion heat dissipation system 110 includes an electric motor 111, a propeller 112, and an arm 113. The electric propulsion heat dissipation system 110 is fixedly connected to one or both of the wing 210 or the fuselage 230 through the arm 113. The propeller 112 is arranged at the output end of the electric motor 111. The electric motor 111 is installed on the arm 113 and can drive the propeller 112 to rotate around its own axis.

[0056] The side surface of the arm 113 facing the propeller 112 is provided with an inlet 1132. The projection (orthographic projection along the axis of the propeller 112) or inclined projection of the blade of the propeller 112 at least partially covers the inlet 1132, so that the airflow generated when the propeller 112 rotates can at least partially cover the inlet 1132. In actual application, this feature can be realized by setting the inlet 1132 as a single opening, for example, the inlet 1132 is set as a circular opening, and the blade projection of the propeller 112 covers the outer edge part thereof. Or the inlet 1132 is set as a rectangular opening, and the blade projection of the propeller 112 covers the central region thereof. In this way, the propeller 112 can suck in the airflow into the inlet 1132 when rotating. The surface of the side of the arm 113 away from the propeller 112 is provided with an outlet 1135. The inlet 1132 is communicated with the outlet 1135 through an assembly space 1131, that is, the airflow can enter the assembly space 1131 through the inlet 1132, pass through the fan motor 1112 and the radiator 1113, and enter the external space (usually the atmospheric environment) through the outlet 1135.

[0057] The electric propulsion heat dissipation system 110 is fixedly connected to the wing 210 or the fuselage 230 of the aircraft through the arm 113, and the electric motor 111 is installed on the arm 113 and drives the propeller 112 to rotate around its own axis. During the rotation of the propeller 112, the area swept by the blades of the propeller 112 generates an airflow, and since the side surface of the arm 113 facing the propeller 112 is provided with an inlet 1132, and the airflow generated by the rotation of the propeller 112 at least partially covers the inlet 1132, the airflow is driven by the rotation of the propeller 112 and guided into the inlet 1132. The incoming airflow then flows through the electric motor 111 in the assembly space 1131, exchanges heat with the heat dissipation components inside the motor, carries away the heat generated during operation, and finally is discharged into the external environment through the outlet 1135 on the side surface of the arm 113 away from the propeller 112. The design of this airflow path enables the establishment of a heat dissipation cycle during the hovering or vertical take-off and landing of the aircraft, avoiding the limitations of relying on natural airflow during flight.

[0058] In a specific embodiment, the propeller 112 can be a three-blade propeller 112 made of carbon fiber composite material, and the arm 113 is made of aluminum alloy material, and the surface of the arm 113 facing the propeller 112 is provided with an inlet 1132, the size and position of which ensure that the projection of the blades of the propeller 112 covers the area of the inlet 1132. The outlet 1135 is arranged on the back side of the arm 113 for discharging the airflow after heat exchange. Further, the assembly space 1131 of the electric motor 111 is provided with a radiator 1113 and a cooling fan 1114, and after the airflow enters through the inlet 1132, it is forced to flow through the surface of the radiator 1113 to achieve effective heat transfer.

[0059] In this regard, the present application further provides that the side surface of the arm 113 facing the propeller 112 is provided with a first inlet 1133 and a second inlet 1134, and the projection of the blades of the propeller 112 on the corresponding surface (i.e. the upper surface) of the arm 113 (the projection along the axis of the propeller 112 is the orthographic projection) at least partially covers one of the first inlet 1133 and the second inlet 1134, that is, the projection of the blades of the propeller 112 on the surface of the arm 113 can cover all of the first inlet 1133 and all of the second inlet 1134, or all of the first inlet 1133 and part of the second inlet 1134, or part of the first inlet 1133 and all of the second inlet 1134, or part of the first inlet 1133 and part of the second inlet 1134, or only all of the first inlet 1133, or only all of the second inlet 1134, or part of the first inlet 1133, or part of the second inlet 1134.

[0060] In actual application, the inlet 1132 refers to an air inlet structure arranged on the surface of the arm 113 towards the propeller 112, which can be realized by adopting a layout mode of two independent openings, for example, the first inlet 1133 and the second inlet 1134 can be asymmetrically distributed or symmetrically distributed, and the purpose thereof is to adapt to the random change of the air flow direction in the hovering state by providing a multi-path air flow channel, and to avoid the air flow capture failure caused by the limitation of a single inlet direction. Wherein, the projection of the blade of the propeller 112 on the corresponding surface of the arm 113 at least partially covers one of the first inlet 1133 and the second inlet 1134, which refers to the overlapping relationship between the projection area of the blade on the surface of the arm 113 and the specific inlet during the rotation of the blade, which can be realized by adopting a fixed coverage ratio or a dynamic switching coverage object, for example, by adjusting the relative position of the inlet or the installation angle of the blade, and the purpose thereof is to convert the air flow field generated by the rotation of the blade into an air inlet driving force, and to specifically enhance the air inlet efficiency of the covered inlet.

[0061] Specifically, the scheme of the present application cooperates the double-inlet structure with the blade coverage characteristics to form an active adaptation mechanism for the heat dissipation system in the hovering working condition. The first inlet 1133 and the second inlet 1134 serve as independent air inlets, and when the attitude of the aircraft changes to cause the change of the air flow direction, the system can always capture effective air flow through at least one inlet. At the same time, the projection of the blade of the propeller 112 on the corresponding surface of the arm 113 at least partially covers one of the first inlet 1133 and the second inlet 1134, so that the air flow field generated by the rotation of the blade can be directionally guided to the covered inlet, for example, the first inlet 1133 is preferentially covered on the windward side to utilize the natural air flow, and the second inlet 1134 is covered on the leeward side to utilize the forced air flow generated by the blade, so as to convert the blade movement into an air inlet driving force, significantly improve the air flow guiding accuracy and stability, and ensure that the heat dissipation system can continuously obtain sufficient air flow in the hovering and vertical take-off and landing working conditions of the aircraft.

[0062] As a specific embodiment, the scheme of the present application is implemented as follows: the arm 113 is provided with the first inlet 1133 and the second inlet 1134 on the surface thereof towards the propeller 112, wherein the first inlet 1133 is located in the front region of the rotation shaft of the propeller 112, and the second inlet 1134 is located in the rear region of the rotation shaft of the propeller 112. The projection of the blade of the propeller 112 on the corresponding surface of the arm 113 at least partially covers the first inlet 1133, the forward air flow generated by the rotation of the blade enters the assembly space 1131 through the first inlet 1133, and the backward air flow generated by the rotation of the blade enters the assembly space 1131 through the second inlet 1134, so as to maintain the continuous supply of the heat dissipation air flow.

[0063] By the above scheme, the application can effectively solve the problem of insufficient supply of cooling airflow caused by unstable airflow direction when the aircraft is in hovering and vertical take-off state, ensure that the heat generated by the electric motor 111 is carried away in time, avoid the risk of overheating caused by heat accumulation, thereby improving the reliability of the electric propulsion cooling system 110 and flight safety.

[0064] In practical applications, in some embodiments of the application, the inlet 1132 includes a first inlet 1133 and a second inlet 1134 to increase the air inlet point. However, in the implementation process, the inlet position is not optimized, resulting in low airflow introduction efficiency during the hovering or vertical take-off phase of the aircraft, making it difficult to fully cool.

[0065] In an embodiment, the first inlet 1133 is arranged on the upper surface of the arm 113 and located in the front side region of the rotating shaft of the propeller 112 (i.e. the front end region of the aircraft). Correspondingly, the second inlet 1134 is arranged on the upper surface of the arm 113 and located in the rear side region of the rotating shaft of the propeller 112 (i.e. the rear end region of the aircraft).

[0066] Specifically, the first inlet 1133 arranged in the front side region of the rotating shaft of the propeller 112 means that the inlet is located in the region directly facing the airflow when the propeller 112 rotates, which can be arranged in the arc region in front of the rotating shaft of the propeller 112, the purpose of which is to capture high-speed airflow to improve air intake efficiency. The second inlet 1134 arranged in the rear side region of the rotating shaft of the propeller 112 means that the inlet is located in the low-pressure region formed by the airflow after flowing around the propeller 112 when the propeller 112 rotates, which can be arranged in the arc region behind the rotating shaft of the propeller 112, the purpose of which is to use low-pressure vortex to ensure balanced airflow entry. More specifically, as shown in Figure 3 , Figure 3 the wind speed diagram corresponding to the different diameter regions of the propeller 112 blades, obviously, the wind speed in the middle region of the propeller 112 blades is larger, therefore, as long as the first inlet 1133 and the second inlet 1134 are arranged in the middle region below the propeller 112, the first inlet 1133 and the second inlet 1134 can have a larger air intake, thereby improving the overall cooling efficiency.

[0067] Specifically, the scheme of the application precisely positions the first inlet 1133 in the front side region of the rotating shaft of the propeller 112, so that the front high-speed airflow generated by the rotation of the propeller 112 can be directly introduced into the first inlet 1133. Since the windward side is a high-pressure region, the air intake is effectively improved. At the same time, the second inlet 1134 is arranged in the rear side region of the rotating shaft of the propeller 112, which uses the low-pressure vortex naturally formed on the leeward side to guide the airflow to enter from the leeward side, preventing airflow accumulation or backflow, thereby ensuring that the airflow can enter the cooling system from both the windward and leeward directions, maintaining stable and sufficient cooling airflow.

[0068] As a preferred embodiment, the scheme of the present application is implemented as follows: when the propeller 112 rotates clockwise, the first inlet 1133 is arranged at the left side area of the rotation shaft of the propeller 112, i.e. the front side area, to capture the airflow impacting from the left side. The second inlet 1134 is arranged at the right side area of the rotation shaft of the propeller 112, i.e. the rear side area, to utilize the low pressure vortex formed at the right side.

[0069] Through the above scheme, the present application can significantly improve the airflow introduction efficiency during the hovering or vertical take-off and landing stage of the aircraft, ensure that the electric motor 111 is sufficiently cooled, avoid damage caused by overheating, and improve flight safety.

[0070] Specifically, in some embodiments of the present application, the first inlet 1133 and the second inlet 1134 are used to introduce airflow for cooling when the propeller 112 rotates. However, in this process, the second inlet 1134 is located at the rear side area, the airflow introduction efficiency is low, and the inflow port 1132 is directly exposed, which can easily cause external debris to enter or the airflow direction to be undesirable, thereby reducing the reliability of the cooling system.

[0071] To this end, as shown in Figures 9-10 , the present application further provides a first grille 114 at the first inlet 1133, which includes a plurality of first guide strips 1141 arranged side by side, and adjacent first guide strips 1141 are arranged at intervals to form first guide gaps 1142. The external airflow can pass through the plurality of first guide gaps 1142 and enter the assembly space 1131, respectively.

[0072] Correspondingly, as shown in Figures 7-8 , the second grille 115 is arranged at the second inlet 1134, which includes a plurality of second guide strips 1151 arranged side by side, and adjacent second guide strips 1151 are arranged at intervals to form second guide gaps 1152. The external airflow can pass through the plurality of second guide gaps 1152 and enter the assembly space 1131, respectively.

[0073] The first grid 114 refers to a flow guide structure arranged at the first inlet 1133, which can be implemented by a metal grid or an engineering plastic grid, aiming to guide the windward side airflow and block external debris from entering. The first flow guide strip 1141 refers to a strip-shaped component arranged side by side in the first grid 114, which can be implemented in different forms such as straight strips, arc-shaped strips or wavy strips, aiming to divide the airflow to reduce flow turbulence. The first flow guide gap 1142 refers to a channel formed between adjacent first flow guide strips 1141, which can be implemented by an equal interval or a gradually changing interval design, aiming to control the airflow direction and maintain the flow efficiency. The second grid 115 refers to a flow guide structure arranged at the second inlet 1134, which can be implemented by the same or different materials and structure forms as the first grid 114, aiming to enhance the capturing ability of the leeward side weak airflow. The second flow guide strip 1151 refers to a strip-shaped component arranged side by side in the second grid 115, which can be implemented by a fixed angle or an adjustable angle flow guide strip, aiming to optimize the airflow entry path. The second flow guide gap 1152 refers to a channel formed between adjacent second flow guide strips 1151, which can be implemented by a fixed width or a variable width design, aiming to adapt to different intensity of airflow conditions.

[0074] Specifically, the scheme of the present application cooperatively configures the first grid 114 and the second grid 115, so that the windward side and the leeward side airflows can be efficiently introduced into the assembly space 1131. The flow guide strips of the first grid 114 form a specific layout according to the blowing direction of the propeller 112, so that the external airflow is divided and guided to smoothly pass through the first flow guide gap 1142 and enter the assembly space 1131, avoiding energy loss caused by direct impact of the airflow. At the same time, the size design of the first flow guide gap 1142 can block the invasion of external debris and ensure the smoothness of the airflow channel. The second grid 115 enhances the capturing ability of weak airflow by the specific design of the second flow guide gap 1152, so that the originally difficult to utilize leeward side airflow is effectively guided into the assembly space 1131, thereby making up for the defect of insufficient air intake. Overall, the first grid 114 and the second grid 115 jointly ensure that the airflow can be stably and efficiently introduced on the windward side and the leeward side, optimizing the airflow management ability of the heat dissipation system.

[0075] As a preferred embodiment, the scheme of the present application is implemented as follows: the first grid 114 adopts a mesh structure woven by metal wires, and the first flow guide strip 1141 is a parallel arranged straight metal strip. The second grid 115 adopts a grid structure formed by polycarbonate injection molding, and the second flow guide strip 1151 is a slightly curved strip-shaped component to better adapt to the flow characteristics of the leeward side airflow.

[0076] Through the above scheme, the air flow introduction efficiency of the rear area is improved, external impurities are effectively prevented from entering the inlet 1132, and the air flow direction is optimized, thereby enhancing the heat dissipation reliability of the electric propulsion heat dissipation system 110 in the hovering and vertical take-off state of the aircraft.

[0077] Specifically, in some embodiments of the above-mentioned application, the first grid 114 is used to guide the external air flow to enter the assembly space 1131 through the guide gap. However, in the implementation process, due to the non-uniform distribution of air flow in the front area, the uniformly arranged first grid 114 is difficult to effectively match the air flow speed change, resulting in low air inlet efficiency and insufficient heat dissipation performance.

[0078] To this end, the application further proposes that the length direction of the first grid 114 is the width direction of the arm 113, and the first grid 114 is arc-shaped, the bending radius of which is the same as the surface radius of the corresponding position of the arm 113. Along the direction from the first inlet 1133 to the second inlet 1134 (which belongs to the length direction of the arm 113), a plurality of first guide strips 1141 are arranged at intervals, and the length of each first guide strip 1141 tends to increase.

[0079] Wherein, the interval arrangement can be understood as an arrangement mode that maintains a physical gap between adjacent first guide strips 1141, which can adopt an equal-interval or non-equal-interval layout form, and the purpose is to maintain the continuous openness of the air flow channel and prevent local air flow blockage. The length of each first guide strip 1141 tends to increase specifically refers to that, from the direction of the first inlet 1133 to the second inlet 1134, the projection size of the first guide strip 1141 perpendicular to the air flow direction gradually expands, which can be achieved by linear gradient or stepwise incremental geometry, and the purpose is to dynamically adapt to the air flow speed gradient change and ensure that the total area distribution of the guide gap matches the air flow intensity.

[0080] Specifically, the scheme of the application keeps the layout direction of the first guide strip 1141 consistent with the actual air flow path generated by the rotation of the propeller 112, so that the guide structure can accurately respond to the air flow dynamic characteristics of the front area. The interval arrangement design ensures the smoothness of the air flow channel while providing a structural basis for length variation, avoiding air flow blockage caused by dense arrangement. The gradually increasing length feature is based on the physical law that the air flow speed decreases from the windward side to the leeward side, and by expanding the distribution density of the guide gap, the air inlet area is increased in the relatively weak air flow area, thereby achieving uniform regulation of air inlet volume.

[0081] By the technical solution, the uneven airflow distribution of the front side region is effectively balanced, the air intake efficiency of the flow guide gap is improved, and the cooling failure problem of the radiator 1113 caused by insufficient local airflow is avoided, thereby ensuring the stable operation of the electric propulsion heat dissipation system 110 during the hovering or vertical take-off and landing stage of the aircraft.

[0082] Further, in an embodiment, the machine arm 113 is defined along a preset cruising direction from one end provided with the first inlet 1133 to one end provided with the second inlet 1134, and the plurality of first flow guide strips 1141 completely cover the orthographic projection of the first inlet 1133 on a plane perpendicular to the preset cruising direction, so that the first flow guide strips 1141 can be stopped on one side of the first inlet 1133 along the preset cruising direction. That is, the first flow guide strips 1141 can be stopped on the front side region of the first inlet 1133, and when the aircraft is cruising, the airflow on the front side will be blocked by the first flow guide strips 1141 of the first grille 114 to avoid the airflow from the front passing through the first grille 114 into the assembly space 1131 of the machine arm 113, thereby reducing the air resistance of the aircraft.

[0083] In the preset cruising direction in the present application, a reference direction is set based on the typical horizontal flight state of the aircraft, which can be defined by the cruising direction of the aircraft, so as to closely match the actual flight conditions in the design of the heat dissipation system and avoid the disconnection between the airflow direction and the system structure. The complete orthographic projection can be understood as that the projection area of the plurality of first flow guide strips 1141 on a plane perpendicular to the preset cruising direction completely covers the projection area of the first inlet 1133, which can be realized by adjusting the arrangement density or quantity distribution of the flow guide strips.

[0084] In actual application, in some embodiments of the present application, the plane of the first inlet 1133 is arranged to guide the external airflow into the heat dissipation system, however, in the implementation process, if the plane of the first inlet 1133 is horizontally arranged, when the aircraft moves along the preset cruising direction, the airflow is easy to directly impact the inlet, which increases the turbulence or foreign matters are easy to invade the assembly space 1131, thereby reducing the heat dissipation efficiency and possibly blocking the flow guide gap, especially when the electric motor 111 generates a large amount of heat during the hovering or vertical take-off and landing stage, which aggravates the risk of overheating.

[0085] To this end, the application further proposes that the plane in which the first inlet 1133 is located is inclined relative to the horizontal plane when the aircraft is in a level flight state, and the height of the plane in which the first inlet 1133 is located gradually increases along the direction from the first inlet 1133 to the second inlet 1134, that is, the first inlet 1133 extends upward and upward. Specifically, in order to achieve the blocking effect of the first flow guide strip 1141, the surface of the first flow guide strip 1141 away from the assembly space 1131 is curved and arc-shaped when arranged, and the angle between the first flow guide strip 1141 and the horizontal plane is greater than the angle between the plane in which the first inlet 1133 is located and the horizontal plane. More specifically, the angle between the plane in which the first inlet 1133 is located and the horizontal plane is between 5° and 30°, and can be 5°, 10°, 20°, 30°, etc. for example, and is not listed one by one. Taking 10° as an example, the angle between the first flow guide strip 1141 and the horizontal plane is greater than 10°, that is, the first flow guide strip 1141 rotates counterclockwise by a certain angle, and the range of the angle greater than 10° is between 1° and 20°, that is, when the angle between the plane in which the first inlet 1133 is located and the horizontal plane is 10°, the angle between the first flow guide strip 1141 and the horizontal plane ranges from 11° to 30°. By analogy, it can be 11°, 20° and 30°, etc. for example, and is not listed one by one.

[0086] It should be noted that the height of the plane in which the first inlet 1133 is located gradually increases along the direction from the first inlet 1133 to the second inlet 1134 can be understood as forming a gradually rising slope structure, which can be achieved in a linear or non-linear increasing manner, and the purpose is to guide the airflow to naturally lift into the inlet area and enhance the kinetic energy of the intake by using the dynamic pressure generated by the flight speed.

[0087] In some embodiments of the application described above, it is proposed that the orthogonal projection of the plurality of first flow guide strips 1141 on the plane perpendicular to the preset level flight direction completely covers the first inlet 1133 to guide the external airflow into the assembly space 1131. However, in the implementation process, the actual blowing direction generated by the rotation of the propeller 112 may deviate from the preset level flight direction, resulting in that the airflow is completely blocked by the flow guide strip and is difficult to pass through the flow guide gap effectively, especially during the hovering or vertical take-off and landing stage of the aircraft. The heat generation of the propeller 112 increases, but the airflow utilization efficiency is low, thereby causing insufficient heat dissipation and the risk of overheating of the electric motor 111.

[0088] To this end, the application further proposes that the blowing direction of the propeller 112 when rotating towards the first inlet 1133 is defined as the first preset air outlet direction, and the projection of the plurality of first flow guide gaps 1142 on the plane perpendicular to the first preset air outlet direction at least partially covers the projection of the first inlet 1133 on the plane perpendicular to the first preset air outlet direction, that is, the first flow guide strip 1141 is difficult to fully block the first flow guide gap 1142 along the first preset air outlet direction, so that the airflow along the first preset air outlet direction can enter the assembly space 1131 through the first flow guide gap 1142, that is, when the propeller 112 rotates, the airflow generated by the propeller 112 can enter the inside of the arm 113 through the first grid 114.

[0089] The first preset air outlet direction refers to the actual airflow direction generated by the propeller 112 when rotating towards the first inlet 1133, which can be dynamically determined based on real-time data fed back by the aircraft attitude sensor, and the purpose is to break away from the dependence on the fixed preset level flight direction, thereby accurately matching the instantaneous airflow path generated in the rotation process of the propeller 112. The projection of the plurality of first flow guide gaps 1142 on the plane perpendicular to the first preset air outlet direction at least partially covers the first inlet 1133, that is, the projection of the first flow guide strip 1141 only covers part of the inlet area rather than all of it, which can be realized by using an array structure of the first flow guide strip 1141 with adjustable inclination, and the purpose is to avoid complete blocking of the airflow and ensure that the first flow guide gap 1142 is aligned with the actual blowing direction to provide an effective flow passage for the airflow.

[0090] Specifically, the scheme of the application defines the first preset air outlet direction as the blowing direction when the propeller 112 is actually working, so that the projection of the plurality of first flow guide strips 1141 only partially covers the first inlet 1133, thereby forming a flow guide gap consistent with the airflow direction. When the forced airflow generated by the rotation of the propeller 112 flows along the first preset air outlet direction, it can directly pass through the flow guide gap and enter the assembly space 1131 without relying on the external airflow generated by the forward speed of the aircraft. This design makes full use of the kinetic energy of the rotation of the propeller 112 itself, maintains a stable airflow passage during the hovering or vertical take-off and landing stage of the aircraft, and effectively guides the airflow to pass through the heat dissipation area of the electric motor 111, thereby achieving timely removal of heat under high load conditions.

[0091] As a specific embodiment, the scheme of the application is implemented as follows: the first flow guide strip 1141 can adopt a movable blade structure made of lightweight alloy material, and the installation angle thereof is linked to the flight control system through a micro servo motor and dynamically adjusted according to the rotation speed signal of the propeller 112, so as to ensure that the first flow guide gap 1142 always aligns with the actual blowing direction during the hovering and vertical take-off and landing stages, thereby maximizing the airflow passing efficiency.

[0092] Through the above scheme, the application effectively solves the problem of heat dissipation channel blockage caused by airflow direction deviation of the aircraft, significantly improves the heat dissipation reliability of the electric motor 111, and reduces the risk of overheating caused by heat accumulation.

[0093] Further, in an embodiment, the flow direction of the first flow guide gap 1142 and the first preset air outlet direction are substantially the same to increase the air intake at the first inlet 1133.

[0094] Wherein, the flow direction of the first flow guide gap 1142 refers to the flow path direction of the airflow through the first flow guide gap 1142, which can be realized by a straight channel or a smooth transition curved channel, depending on the airflow guiding requirement. The first preset air outlet direction refers to the blowing direction of the propeller 112 towards the first inlet 1133 when rotating, which is determined by the rotation direction and installation angle of the propeller 112, aiming to guide the airflow to enter the assembly space 1131 efficiently and avoid energy loss caused by direction deviation.

[0095] Specifically, the scheme of the application sets the flow direction of the first flow guide gap 1142 to be completely consistent with the first preset air outlet direction, so that the airflow generated by the rotation of the propeller 112 does not need to change the flow direction when passing through the first flow guide gap 1142, thereby eliminating the conditions for the generation of airflow separation and vortex phenomenon. This design ensures that the airflow enters the assembly space 1131 directly in a continuous and concentrated state, effectively maintaining the kinetic energy and stability of the airflow, and further improving the cooling efficiency of the electric motor 111 and the radiator 1113.

[0096] Specifically, in some embodiments of the application described above, a flow guide channel is used to optimize the airflow path. However, in the implementation process, the direct communication between the inlet 1132 and the assembly space 1131 leads to uneven airflow distribution and increased flow resistance, especially during the hovering or vertical take-off and landing stage of the aircraft, the external airflow introduction efficiency is low, it is difficult to fully cover the surface of the radiator 1113, causing insufficient heat dissipation of the electric motor 111, which is prone to overheating failure.

[0097] To this end, as Figures 12-13As shown, the application further proposes that the arm 113 is provided with a first flow guide passage part 1136, and the first inlet 1133 is communicated with the assembly space 1131 through the first flow guide passage part 1136. It should be noted that one end of the first flow guide passage part 1136 is sealingly connected to the side of the first inlet 1133, and the other end is sealingly connected to the corresponding opening of the assembly space 1131. The arm 113 is provided with a second flow guide passage part 1137, and the second inlet 1134 is communicated with the assembly space 1131 through the second flow guide passage part 1137. It should be noted that one end of the second flow guide passage part 1137 is sealingly connected to the side of the second inlet 1134, and the other end is sealingly connected to the corresponding opening of the assembly space 1131.

[0098] Among them, the first flow guide passage part 1136 refers to the flow guide structure connecting the first inlet 1133 and the assembly space 1131, which can be realized by a straight channel, a curved channel or a tapered channel, aiming to guide the windward side airflow to smoothly transition, avoid airflow separation and reduce flow resistance. The second flow guide passage part 1137 refers to the flow guide structure connecting the second inlet 1134 and the assembly space 1131, which can be realized by a rectangular channel, an arc-shaped channel or a channel with flow guide vanes, aiming to compensate for the low-pressure environment on the leeward side to prevent airflow backflow or stagnation, thereby balancing the overall airflow distribution.

[0099] Specifically, the scheme of the application orderly guides the airflow introduced by the first inlet 1133 in the front side region of the propeller 112 rotating shaft through the first flow guide passage part 1136, and uses the airflow power generated by the rotation of the propeller 112 to make the airflow smoothly transition to the assembly space 1131 along the preset level flight direction. At the same time, the second flow guide passage part 1137 is arranged for the second inlet 1134 in the rear side region of the propeller 112 rotating shaft, and collects weak airflow through the structured channel and accelerates to introduce the airflow into the assembly space 1131, ensuring that the airflow uniformly covers the surface of the radiator 1113 under the whole attitude of the aircraft. Overall, the first flow guide passage part 1136 and the second flow guide passage part 1137 work together to change the originally disordered airflow path into orderly guidance, significantly improving the airflow introduction efficiency and the uniformity of heat dissipation.

[0100] As a preferred embodiment, the scheme of the application is implemented as follows: the first flow guide passage part 1136 is designed in the shape of a Venturi tube with gradually tapered and gradually expanded shape, and the inner wall surface is provided with a smoothly transitioned flow guide curved surface to accelerate the windward side airflow and reduce turbulence. The second flow guide passage part 1137 is designed as a rectangular channel with inclined flow guide vanes, and the flow guide vanes are arranged in an arc shape along the airflow direction to prevent the leeward side airflow from separating and enhance the airflow collection capacity. The first inlet 1133 and the second inlet 1134 are respectively communicated to the assembly space 1131 through the above-mentioned channel structure inside the arm 113, ensuring that the airflow is accurately guided to the areas of the heat dissipation fan 1114 and the radiator 1113.

[0101] Through the above scheme, the application effectively improves the external airflow introduction efficiency in the hovering or vertical take-off stage of the aircraft, the airflow distribution is more uniform, and the flow resistance is significantly reduced, and the surface of the radiator 1113 is sufficiently cooled, thereby avoiding overheating failure of the electric motor 111 due to insufficient heat dissipation, and ensuring stable operation of the electric propulsion system.

[0102] In some embodiments of the application described above, a flow guide channel portion is provided to communicate the inlet and the assembly space 1131. However, in this process, the opening direction is not oriented to the heat dissipation fan 1114 and the radiator 1113, resulting in uneven airflow distribution and low heat dissipation efficiency. Especially in the hovering and vertical take-off flight stage of the aircraft, when the airflow power is insufficient, the heat dissipation performance is difficult to meet the high heat load demand of the electric motor 111.

[0103] To this end, the application further provides that along the air inlet direction from the first inlet 1133 to the assembly space 1131, the flow area of the first flow guide channel portion 1136 increases, that is, the first flow guide channel portion 1136 is trumpet-shaped as a whole, so that the opening of the first flow guide channel portion 1136 in the assembly space 1131 is arranged towards the heat dissipation fan 1114 and the radiator 1113. Further, along the air inlet direction from the second inlet 1134 to the assembly space 1131, the flow area of the second flow guide channel portion 1137 increases, that is, the second flow guide channel portion 1137 is trumpet-shaped as a whole, so that the opening of the second flow guide channel portion 1137 in the assembly space 1131 is arranged towards the heat dissipation fan 1114 and the radiator 1113.

[0104] In practical application, the increasing trend of the flow area is to gradually expand the cross-sectional area of the flow guide channel portion from the inlet to the assembly space 1131, which can be realized by using a tapered expansion channel, a stepped expansion channel or a curved expansion channel, the purpose of which is to reduce airflow speed, reduce turbulence and energy loss, and make the airflow more smoothly transition to the assembly space 1131. Wherein, the opening arranged towards the heat dissipation fan 1114 and the radiator 1113 can be understood as the outlet of the flow guide channel portion in the assembly space 1131 directly aiming at the heat dissipation fan 1114 and the radiator 1113, which can be realized by adjusting the outlet angle of the channel, setting guide vanes or optimizing the channel shape, the purpose of which is to ensure that the airflow concentrates on the key heat dissipation area, avoiding airflow scattering or deviating from the heat source, thereby improving heat exchange efficiency.

[0105] Specifically, the scheme of the application is designed by increasing the flow area of the first and second flow guide channel sections 1136 and 1137, so that the airflow naturally decays in speed based on the geometric characteristics of the expanding channel before entering the assembly space 1131, thereby reducing the intensity of turbulent flow and reducing energy loss. At the same time, the trend of the flow area change directly guides the opening direction to accurately point to the cooling fan 1114 and the radiator 1113, ensuring that the airflow can cover the key cooling area of the radiator 1113 after entering the inlet. When the aircraft is in a hovering and vertical take-off state, the airflow is weak, and this design can make full use of limited airflow resources to ensure that the surface of the radiator 1113 is uniformly and continuously covered with cooling airflow, effectively addressing the cooling challenges of the electric motor 111 under high load conditions.

[0106] As a specific embodiment, the scheme of the application is implemented as follows: the first flow guide channel section 1136 can be specifically designed as a horn-shaped expanding channel with smooth inner walls, and the opening in the assembly space 1131 is rectangular, with the long side parallel to the rotation axis of the cooling fan 1114, so that the airflow is uniformly distributed on the surface of the radiator 1113. The second flow guide channel section 1137 can adopt a similar structure, and the opening direction is adjusted to be consistent with the arrangement direction of the cooling fins of the radiator 1113, thereby strengthening the directional flow of the airflow in the assembly space 1131.

[0107] Through the above technical scheme, the airflow distribution is more uniform, and the heat exchange efficiency is significantly improved, especially during the flight phase of the aircraft in hovering and vertical take-off, which can effectively meet the high heat load demand of the electric motor 111 and prevent overheating damage.

[0108] But not limited to this, in other embodiments, the flow area of the first flow guide channel section 1136 can also be constant or decreasing, and correspondingly, the flow area of the second flow guide channel section 1137 can also be constant or decreasing.

[0109] In actual application, in some embodiments of the application described above, the second inlet 1134 is arranged at the rear side region of the rotation shaft of the propeller 112, which is used to introduce external airflow to assist cooling during the flight phase of the aircraft in hovering and vertical take-off. However, in the implementation process, when the length of the second grille 115 is inconsistent, it will cause uneven airflow distribution at the rear side region, especially the airflow on the leeward side is weak, and the local length change of the grille will exacerbate the airflow resistance difference, causing the air intake efficiency to decrease, and then causing the electric motor 111 to be insufficiently cooled, threatening flight safety.

[0110] To this end, the second grid 115 has a length direction that is the width direction of the arm 113, and the second grid 115 is arc-shaped, the bending radius of which is the same as the surface radius at the corresponding position of the arm 113, a plurality of second flow guide strips 1151 are arranged at intervals along the direction from the first inlet 1133 to the second inlet 1134 (which is the length direction of the arm 113), and the length of each second flow guide strip 1151 is the same.

[0111] The plurality of second grids 115 arranged at intervals means that the second grids 115 are arranged in parallel at uniform intervals, which can be realized by flow guide strips made of metal or plastic arranged at equal intervals, and the purpose is to form a plurality of independent flow guide channels to avoid the concentration or short circuit of airflow in the rear area. The length of each second grid 115 being the same means that the size of all second grids 115 is consistent, which can be realized by flow guide strips produced by standardized manufacturing processes, and the purpose is to eliminate the local resistance changes caused by length differences and make the flow characteristics of each flow guide gap uniform.

[0112] Specifically, the scheme of the present application arranges a plurality of second grids 115 with the same length at intervals along the preset flat flight direction, so that in the hovering state of the aircraft, the airflow in the rear area can uniformly pass through each flow guide gap into the assembly space 1131. Since all second grids 115 have the same length, the resistance characteristics of each flow guide gap are consistent, thereby avoiding the problem of uneven airflow distribution and ensuring that the heat sink 1113 obtains stable and uniform airflow, effectively improving the heat dissipation efficiency.

[0113] As a preferred embodiment, the scheme of the present application is implemented as follows: The second grid 115 can be made of lightweight aluminum alloy material and installed in parallel at the second inlet 1134 at equal intervals, and the length of each second grid 115 is the same. When the propeller 112 rotates, the airflow on the leeward side smoothly flows into the assembly space 1131 through these uniformly distributed flow guide gaps, thereby dissipating heat for the electric motor 111.

[0114] Through the above scheme, the present application can effectively solve the problem of uneven airflow distribution in the rear area, ensure stable air intake efficiency during the flight phase of the aircraft in hovering and vertical take-off and landing, prevent the electric motor 111 from overheating due to insufficient heat dissipation, and thereby improve flight safety and system reliability.

[0115] Specifically, in some embodiments of the application described above, the second inlet 1134 is provided to introduce airflow at the rear region of the propeller 112 shaft, however, in the implementation process, the direction of the plane where the second inlet 1134 is located is not specified, which may cause the second inlet 1134 to be difficult to effectively capture the leeward airflow generated by the propeller 112 due to changes in flight attitude or unstable airflow direction during the hovering or vertical take-off and landing stage of the aircraft, resulting in reduced air intake efficiency and insufficient heat dissipation capacity, thereby increasing the risk of overheating of the electric motor 111.

[0116] To this end, the application further provides that the plane where the second inlet 1134 is located and the shape of the outer contour of the arm 113 are the same, for example, when the shape of the outer contour of the arm 113 at the corresponding position is a plane, the plane where the second inlet 1134 is located is a plane, and when the aircraft is in a level flight state, the plane where the second inlet 1134 is located is parallel or approximately parallel to the horizontal plane. In practical applications, the plane where the second inlet 1134 is located refers to the opening plane of the rear region of the arm 113 for introducing airflow, which can be implemented by complete horizontal setting or approximate horizontal setting, the purpose of which is to ensure that during the key flight stage of the aircraft, the plane is naturally aligned with the direction of the leeward airflow generated by the propeller 112, avoiding airflow deflection or increased resistance caused by tilting, thereby ensuring smooth airflow into the assembly space 1131.

[0117] Specifically, the scheme of the application sets the plane where the second inlet 1134 is located to be parallel to the horizontal plane, so that when the aircraft is in a vertical take-off and landing state, a hovering state, and a tilting state, the plane is aligned with the direction of the leeward airflow generated by the rotation of the propeller 112, thereby reducing the flow resistance when the airflow enters. At the same time, this design fully utilizes the airflow power generated by the propeller 112 itself, ensuring that when the aircraft is in a hovering and vertical take-off and landing state, the external airflow can pass through the second inlet 1134 into the assembly space 1131 without obstruction, effectively improving the air intake reliability of the rear region.

[0118] However, without limitation, in other embodiments, when the shape of the outer contour of the arm 113 at the corresponding position is a curved surface, the plane where the second inlet 1134 is located is a curved surface to adapt to the shape of the outer contour of the arm 113 at the corresponding position.

[0119] In summary, with such a setting, the following beneficial effects are achieved: the plane where the second inlet 1134 is located is continuously transitioned with the outer contour of the arm 113, avoiding sharp edges or protrusions, which can significantly reduce the turbulence generated when the airflow passes through the second inlet 1134. Moreover, the smooth curved surface design allows the airflow to more smoothly adhere to the surface of the arm 113, reducing local low-pressure areas and thereby reducing overall aerodynamic drag, which directly translates into longer endurance or lower energy consumption.

[0120] Further, the second inlet 1134 can be shaped according to the flow field characteristics around the arm 113 to guide the flow, introduce more free flow air into the second inlet 1134, and avoid flow impact, rebound or overflow due to the mismatch between the second inlet 1134 and the surface of the arm 113, ensuring that more flow effectively enters the second inlet 1134.

[0121] Specifically, in some embodiments of the application described above, the second inlet 1134 is proposed to introduce external airflow, however, in the implementation process, the actual blowing direction generated by the rotation of the propeller 112 is not considered in the design of the flow guide strip, which makes it difficult for the airflow to efficiently pass through the flow guide gap and enter the assembly space 1131. Especially during the hovering or vertical take-off and landing stage of the aircraft, the propeller 112 generates airflow but the direction does not match the orientation of the flow guide strip, causing airflow scattering or blocking, significantly reducing the cooling efficiency and increasing the risk of overheating of the electric motor 111.

[0122] To this end, the application further proposes that the blowing direction of the propeller 112 towards the second inlet 1134 when rotating is defined as a second preset air outlet direction, and the orthogonal projection of the plurality of second flow guide gaps 1152 in the plane perpendicular to the second preset air outlet direction at least partially covers the orthogonal projection of the second inlet 1134 in the plane perpendicular to the second preset air outlet direction, so that the airflow along the second preset air outlet direction can enter the assembly space 1131 through the second flow guide gap 1152. That is, when the propeller 112 rotates, the airflow generated by the propeller 112 can enter the interior of the arm 113 through the second grid 115.

[0123] The second preset air outlet direction refers to the dynamic direction of the airflow actually blowing towards the second inlet 1134 when the propeller 112 rotates, which can be determined based on real-time calculation of the propeller 112 rotation speed and blade angle, or can be pre-calibrated through wind tunnel experiments, with the purpose of dynamically matching the airflow direction to avoid rigid design. The orthogonal projection of the plurality of second flow guide gaps 1152 in the plane perpendicular to the second preset air outlet direction at least partially covers the orthogonal projection of the second inlet 1134 in the plane, which is a guide flow strip layout that forms a non-completely blocked channel structure in the airflow direction reference system, which can be implemented by an array of inclined metal strips or composite flow guide pieces 1501, with the purpose of preventing airflow from being completely blocked and avoiding scattering, ensuring the directional guiding ability of the flow guide gap to the airflow in a specific direction.

[0124] Specifically, the scheme of the present application defines the second preset air outlet direction as the actual air blowing direction generated by the rotation of the propeller 112, so that the layout of the second guide strip 1151 is strictly aligned with the dynamic air flow characteristics. On this basis, the plurality of second guide gaps 1152 partially cover the second inlet 1134 in the projection plane perpendicular to the direction, forming a guide channel matched with the air flow direction, so that the air flow generated by the propeller 112 in the hovering state can directly pass through the second guide gap 1152 along the second preset air outlet direction, avoiding scattering or blocking due to direction deviation. This design organically cooperates with the structure of the second inlet 1134, so that the air flow can still be efficiently introduced into the assembly space 1131 without the forward speed of the aircraft, thereby ensuring the continuous operation ability of the heat dissipation system.

[0125] As a preferred embodiment, the scheme of the present application is implemented as follows: the second guide strip 1151 is made of lightweight aluminum alloy material, and its arrangement direction is strictly set according to the actual measured air blowing direction of the propeller 112 in the hovering working condition. In the reference plane perpendicular to the air blowing direction, the projection of the second guide strip 1151 covers 60% to 80% of the projection area of the second inlet 1134, forming uniformly distributed second guide gaps 1152. When the propeller 112 rotates, the air flow flows along the second preset air outlet direction, and the opening direction of the second guide gap 1152 is consistent with the air flow direction, so that the air flow smoothly passes through the gap into the assembly space 1131, and the uncovered projection area allows part of the air flow to naturally diffuse to maintain pressure balance.

[0126] Through the above scheme, the present application can effectively utilize the air flow generated by the rotation of the propeller 112 itself during the hovering or vertical take-off and landing stage of the aircraft, and significantly improve the introduction efficiency of the air flow through the second guide gap 1152 by precisely matching the blowing direction, reduce the scattering loss of the air flow, and ensure that the heat dissipation system obtains continuous and stable cooling air flow, thereby relieving the overheating risk of the electric motor 111 in the hovering and vertical take-off and landing working conditions.

[0127] In practical application, in some embodiments of the present application, the second guide gap 1152 is used to guide the air flow into the assembly space 1131 along the second preset air outlet direction, however, during the implementation process, the direction of the air flow entering the assembly space 1131 may not match the air flow demand of the radiator 1113, resulting in insufficient heat dissipation efficiency during the hovering and vertical take-off and landing stage of the aircraft, and it is difficult to effectively cope with the heat dissipation demand of the electric motor 111 in the high heat production state.

[0128] To this end, the application further proposes that the second guide gap 1152 extends in an arc shape along the guide direction of the airflow in the second guide gap 1152, and the flow direction of the airflow at the opening of the second guide gap 1152 close to the propeller 112 and the second preset air outlet direction are substantially the same, so as to increase the air intake at the second inlet 1134, and the flow direction of the airflow at the opening of the second guide gap 1152 close to the assembly space 1131 is vertically downward.

[0129] Wherein, the arc-shaped extension of the second guide gap 1152 refers to that the channel shape of the guide gap is a continuous curve along the airflow direction, which can be realized by a circular arc or a parabolic channel structure, and the purpose is to realize smooth turning of the airflow during flow to avoid turbulence and energy loss caused by sudden change of direction. The flow direction of the airflow at the opening of the second guide gap 1152 close to the propeller 112 and the second preset air outlet direction are the same, which means that the inlet direction is consistent with the fixed blowing direction generated by the rotation of the propeller 112, which can be realized by adjusting the inclination angle or curvature of the second guide strip 1151, and the purpose is to efficiently capture the wind pressure generated by the propeller 112 thrust effect, reduce the inlet resistance and enhance the air intake efficiency. The flow direction of the airflow at the opening of the second guide gap 1152 close to the assembly space 1131 is vertically set, which means that the outlet direction is perpendicular to the horizontal plane, which can be realized by designing the bending shape of the end of the guide gap, and the purpose is to guide the airflow to the vertical direction to adapt to the typical vertical layout requirement of the radiator 1113.

[0130] Specifically, in some embodiments of the application described above, the projection relationship between the radiator 1113 and the outflow port 1135 is used to optimize the heat dissipation airflow path, however, in the implementation process, if the position of the radiator 1113 on the arm 113 and the outflow port 1135 do not form an effective match, it may be difficult for the airflow to flow through the surface of the radiator 1113, causing heat accumulation and reducing the heat dissipation efficiency, especially when the aircraft is hovering or vertical take-off and landing, the electric motor 111 generates more heat, which is prone to cause overheating risk, threatening the safe operation of the system.

[0131] To this end, the application further proposes that the orthographic projection of the heat sink 1113 on the surface corresponding to the arm 113 (i.e., the lower surface) at least partially coincides with the outflow port 1135, or the orthographic projection of the heat sink 1113 on the surface corresponding to the arm 113 (i.e., the lower surface) is completely covered by the outflow port 1135. Among them, the orthographic projection of the heat sink 1113 on the surface corresponding to the arm 113 at least partially coincides with the outflow port 1135, which means that the projection area of the heat sink 1113 and the projection area of the outflow port 1135 have a spatial intersection, which can be realized by the layout method that part of the area of the heat sink 1113 is located directly below the outflow port 1135, and the purpose is to guide part of the hot air flow to directly target the outflow port 1135 for exhaust, avoiding local air flow retention. The orthographic projection of the heat sink 1113 on the surface corresponding to the arm 113 is completely covered by the outflow port 1135, which means that the projection area of the heat sink 1113 is entirely located within the projection area of the outflow port 1135, which can be realized by the layout method that the size of the outflow port 1135 is greater than the size of the heat sink 1113, and the purpose is to constrain all the hot air flow generated by the heat sink 1113 within the range of the outflow port 1135, preventing heat leakage or backflow to non-target areas, thereby improving the concentration of air flow guidance.

[0132] Specifically, the scheme of the application precisely regulates the spatial layout relationship between the heat sink 1113 and the outflow port 1135, so that the hot air flow generated by the heat sink 1113 can be directly exhausted to the outflow port 1135, avoiding the disordered diffusion of the air flow in the assembly space 1131. The partially coinciding projection relationship is based on the geometric characteristics of the surface of the arm 113, making the air flow path more consistent with the principles of fluid dynamics, reducing flow resistance, and the completely covering projection relationship further strengthens the concentrated guidance of the air flow, constraining the hot air flow within the range of the outflow port 1135, significantly improving the continuity of the air flow between the heat sink 1113 and the outflow port 1135, thereby realizing efficient heat dissipation using limited air flow resources when the aircraft is in a hovering and vertical take-off state.

[0133] In some embodiments of the application described above, the design of the position coincidence of the heat sink 1113 and the outflow port 1135 is proposed to ensure effective heat dissipation, however, in the implementation process, the outflow port 1135 lacks structured flow guiding and protection mechanism, resulting in turbulent flow and unstable heat dissipation efficiency when the air flow is exhausted, and may cause system blockage or damage due to external foreign matter intrusion, especially during the hovering and vertical take-off flight phase of the aircraft, the heat dissipation performance is significantly reduced, threatening the safe operation of the system.

[0134] To this end, as shown in FIG. 11, the application proposes a heat dissipation structure 1100, which comprises a heat sink 1113 and an outflow port 1135, and the heat sink 1113 and the outflow port 1135 are arranged on the surface corresponding to the arm 113 of the aircraft. Figure 11As shown, the application further proposes that a third grid 116 is arranged at the outflow port 1135, and the third grid 116 includes a plurality of third flow guide strips 1161 arranged side by side, and the adjacent third flow guide strips 1161 are arranged at intervals to form third flow guide gaps 1162, and the airflow passing through the heat sink 1113 can pass through the plurality of third flow guide gaps 1162 and enter the external space.

[0135] The third grid 116 refers to a flow guide structure arranged at the outflow port 1135, which can be realized by a metal mesh structure or a plastic grid, and the purpose is to provide structural support and guide the orderly discharge of airflow. The third flow guide strip 1161 can be understood as a strip-shaped component arranged side by side in the third grid 116, which can be realized by a linear or arc cross-section, and the purpose is to divide the hot airflow into multiple stable flow beams. The third flow guide gap 1162 is specifically the interval between adjacent third flow guide strips 1161, which can be arranged as uniform or gradually changing width to realize, and the purpose is to control the speed distribution when the airflow passes through, avoid local turbulent flow formation and enhance the system protection capability.

[0136] Specifically, the scheme of the application realizes the integrated arrangement of the third grid 116 and the outflow port 1135, so that the hot airflow passing through the heat sink 1113 is naturally divided into multiple parallel flow beams during the discharge process by the third flow guide strips 1161. These flow beams are stably guided into the external space through the directional guidance of the third flow guide gap 1162, thereby suppressing the fluctuation of heat dissipation efficiency caused by the disordered diffusion of airflow. At the same time, the physical barrier effect of the third grid 116 effectively blocks the intrusion path of external foreign matters, prevents system blockage, especially maintains the continuity and uniformity of the heat dissipation airflow in the hovering state of the aircraft, and ensures the efficient heat exchange function of the heat sink 1113.

[0137] As a preferred embodiment, the scheme of the application is implemented as follows: the third grid 116 can be specifically a grid structure made of stainless steel, and the third flow guide strips 1161 are arranged in a straight line and the gap width between adjacent flow guide strips is substantially uniform. This structure can ensure that the hot airflow is uniformly divided and discharged along the preset direction smoothly, and effectively blocks the entry of external particulate matter into the heat dissipation system.

[0138] Through the above scheme, the application significantly improves the stability of the heat dissipation airflow and the reliability of the system protection during the hovering and vertical take-off and landing flight phases of the aircraft, effectively avoids the decline of heat dissipation efficiency and the risk of system failure caused by airflow turbulence and foreign matter intrusion, thereby ensuring the safe operation of the electric propulsion heat dissipation system 110.

[0139] Specifically, the flow guide direction of the third flow guide gap 1162 is vertically arranged to ensure that the heat sink 1113 can better discharge the high-temperature airflow, reduce the flow of high-temperature airflow along the lower wall surface of the fixed rotor, and avoid the reduction of the service life of the wall surface of the wing 210 under the influence of high-temperature thermal load.

[0140] In the current eVTOL electric propulsion system, the airflow path design of the cooling system has significant defects, which causes the heat generated by the fan motor during continuous operation to be difficult to cool in time and effectively. Specifically, due to the unreasonable relative position layout of the fan motor and the power motor, the external airflow is difficult to directly pass through the fan motor body for forced heat dissipation, so that the heat inside the fan motor is continuously accumulated. This problem directly affects the thermal management reliability of the cooling system, and further causes the working temperature of the fan motor to exceed the safe threshold range, which may eventually trigger system-level failure risk.

[0141] For example, when the eVTOL performs high-load tasks (such as vertical take-off and hovering, etc.), the fan motor of the fixed rotor generates a large amount of heat due to the continuous operation of the heat dissipation fan, but since it is arranged between the power motor and the radiator and lacks effective airflow channels, the external cooling airflow can only flow through the surface of the fan motor and is difficult to penetrate the internal structure of the fan motor. The heat is continuously accumulated in the winding and stator core of the fan motor, causing the temperature of the fan motor to rise rapidly, which in turn triggers the over-temperature protection mechanism and stops the operation. This phenomenon directly interrupts the operation of the heat dissipation fan, causing the radiator to be difficult to obtain sufficient airflow for heat exchange, and the cooling efficiency of the power motor is significantly reduced.

[0142] If the above problems are not solved, the heat accumulation of the fan motor will inevitably cause the accelerated aging of the motor insulation material, the failure of the bearing lubrication, and other technical consequences. As a result, the failure probability of the fan motor will be greatly increased, which in turn causes the heat dissipation fan to stop working, so that the entire cooling system loses the heat dissipation ability of the power motor. The power motor continues to heat up due to the difficulty in timely heat transfer, which may cause serious failures such as demagnetization of the permanent magnet or short circuit of the winding, and ultimately threatens the flight stability of the aircraft and the safety of the passengers.

[0143] To this end, as shown in the Figure 2 application, an electric motor 111 is provided, which includes a power motor 1111, a fan motor 1112, a heat dissipation fan 1114, and a radiator 1113. A propeller 112 is arranged at the output end of the power motor 1111, so that the power motor 1111 can drive the propeller 112 to rotate. The fan motor 1112 is used to drive the heat dissipation fan 1114 to rotate. Specifically, the heat dissipation fan 1114 is connected to the side of the fan motor 1112 away from the power motor 1111, and the heat dissipation fan 1114 is connected to the output end of the fan motor 1112, that is, in Figure 2In the embodiment, the heat dissipation fan 1114 is located below the fan motor 1112. The radiator 1113 cools the power motor 1111 through circulation of the cooling liquid, and the radiator 1113 is arranged on the air outlet side of the heat dissipation fan 1114, specifically, the radiator 1113 is arranged on the side of the heat dissipation fan 1114 away from the power motor 1111, so that the air blown by the heat dissipation fan 1114 can directly pass through the radiator 1113. The arm 113 is provided with an assembly space 1131, and the fan motor 1112, the heat dissipation fan 1114, the radiator 1113 and at least part of the power motor 1111 are all installed in the assembly space 1131. It should be noted that the assembly space 1131 specifically refers to the installation area of the fan motor 1112, the heat dissipation fan 1114, the radiator 1113 and at least part of the power motor 1111 in the arm 113, rather than the internal space of the entire arm 113. The installation space between the fan motor 1112 and the power motor 1111 is provided with a communication flow inlet 1132, and the fan motor 1112 is provided with a cooling channel 1201 for passing external airflow, so that the airflow in the installation space can pass through the cooling channel 1201, pass through the fan motor 1112 and flow towards the radiator 1113, thereby achieving heat dissipation of the cooling liquid in the radiator 1113.

[0144] In this embodiment, to solve the problem that the heat generated by the fan motor 1112 during continuous operation is difficult to cool in time and effectively, the fan motor 1112 is provided with a cooling channel 1201 for cooling by external airflow. In actual application, the cooling channel 1201 refers to an airflow guiding path designed inside and / or outside the fan motor 1112, which can be realized by a hole or groove structure formed on the shell of the fan motor 1112, for example, a plurality of holes or grooves are arranged on the axial end face and the peripheral side wall of the shell of the fan motor 1112, or a channel is formed by a ventilation cavity reserved in the stator core of the fan motor 1112, which is mainly to enable the external airflow to directly pass through the body of the fan motor 1112 to forcibly cool the winding and heat generating components. Further, after the airflow passing through the body of the fan motor 1112 enters the side of the fan motor 1112 close to the radiator 1113, it can also pass through the radiator 1113 and cool the radiator 1113. Further, the fan motor 1112 and the power motor 1111 have a mounting interval therebetween, specifically, the mounting interval refers to the physical gap between the fan motor 1112 and the power motor 1111, for example, a fixed distance is maintained between the rear end face of the power motor 1111 and the front end face of the fan motor 1112, which is mainly to provide a natural inlet for external airflow to avoid airflow blockage. Therefore, the airflow in the mounting interval can pass through the fan motor 1112 through the cooling channel 1201 and flow towards the radiator 1113, thereby effectively taking away the heat generated by the fan motor 1112 during operation and avoiding the risk of failure caused by heat accumulation. Specifically, this design optimizes the airflow path to enable the external airflow to directly cool the body of the fan motor 1112 during passing through the fan motor 1112, while ensuring that the cooled airflow continues to flow to the radiator 1113 to assist in improving the overall heat dissipation efficiency. Moreover, the heat dissipation fan 1114 and the power motor 1111 are arranged with an interval therebetween to form an air inlet area for the external airflow to enter.

[0145] Specifically, in an embodiment, the power motor 1111 can be specifically a permanent magnet synchronous motor, the heat dissipation fan 1114 adopts an axial flow design, and the radiator 1113 is composed of aluminum radiating fins. In this configuration, the airflow in the mounting interval passes through the cooling channel 1201 of the fan motor 1112 to directly cool the body of the fan motor 1112, while ensuring that the cooled airflow continues to flow to the radiator 1113.

[0146] Therefore, the technical scheme optimizes the air flow path design, so that the external air flow can directly pass through the fan motor 1112 for cooling, effectively solving the problem that the heat generated by the fan motor 1112 during continuous operation is difficult to cool in time. The heat generated by the fan motor 1112 is taken away in time, avoiding the risk of failure caused by heat accumulation. At the same time, the cooled air flow continues to flow to the radiator 1113, assisting the radiator 1113 in heat dissipation of the motor 1111, thereby improving the overall heat dissipation reliability of the system and preventing the motor 1111 from being affected by the failure of the fan motor 1112 and the flight safety.

[0147] In some embodiments of the present application, as shown in Figures 14-16 The cooling channel 1201 is provided to pass the air flow through the fan motor 1112 for heat dissipation, however, in the implementation process, the inlet of the cooling channel 1201 is designed single, resulting in uneven distribution of the air flow, which is difficult to fully cover the circumferential area of the fan motor 1112, causing local heat accumulation, thereby affecting the cooling efficiency of the fan motor 1112 and the operation safety of the entire electric propulsion system.

[0148] To this end, the present application further provides that the cooling channel 1201 includes an axial inlet 1202, a radial inlet 1203 and an axial outlet 1204, the axial inlet 1202 is arranged on the axial side end face of the fan motor 1112 close to the motor 1111 and communicates with the installation interval, the axial outlet 1204 is arranged on the opposite side of the axial inlet 1202, that is, the axial outlet 1204 is arranged on the axial side end face of the fan motor 1112 close to the radiator 1113, and the axial outlet 1204 and the radiator fan 1114 are correspondingly arranged, the flow area of the axial outlet 1204 and the radiator fan 1114 are matched, so that the air flow can enter the cooling channel 1201 through the axial inlet 1202 and the radial inlet 1203, and flow out of the cooling channel 1201 from the axial outlet 1204. The axial inlet 1202 refers to the air inlet structure arranged on the axial end face of the fan motor 1112, which can be realized in the form of an annular groove or a polygonal hole array, the purpose is to efficiently guide the air flow in the installation interval into the cooling channel 1201, avoiding the air flow stagnation or vortex in this area. The radial inlet 1203 refers to the air inlet structure arranged on the outer circumferential side wall of the fan motor 1112, which can be realized in the form of an arc-shaped gap continuously distributed along the circumference or a discrete hole group, the purpose is to introduce supplementary air flow from the external environment, ensuring uniform coverage of the circumferential area of the fan motor 1112. The axial outlet 1204 refers to the air outlet structure arranged on the axial end face of the fan motor 1112 close to the radiator 1113, which can be realized in the form of a gradually expanding flow channel or a multi-hole diffuser, the purpose is to unify the air flow direction and enhance the heat exchange matching with the radiator 1113.

[0149] Specifically, the scheme of the application forms a multi-path confluence of axial airflow from the mounting interval and radial airflow from the external environment in the cooling channel 1201 through the composite layout of the axial inlet 1202 and the radial inlet 1203, and the mixed airflow is guided to the radiator 1113 along the axial outlet 1204, thereby optimizing the uniformity of airflow distribution in the circumferential direction of the fan motor 1112, effectively avoiding local heat accumulation, and improving the overall thermal management capability of the heat dissipation system.

[0150] As a preferred embodiment, the scheme of the application is implemented as follows: the axial inlet 1202 is specifically an annular groove structure arranged on the front end surface of the fan motor 1112, the radial inlet 1203 is specifically an array of arc-shaped slits uniformly distributed on the outer peripheral side wall of the fan motor 1112, and the axial outlet 1204 is specifically a corresponding porous diffuser structure on the rear end surface of the fan motor 1112. After the airflow enters the cooling channel 1201 through the annular groove and the arc-shaped slits at the same time, it flows out to the radiator 1113 along the axial direction, thereby achieving efficient cooling of the fan motor 1112.

[0151] Through the above scheme, the application solves the problem of uneven airflow distribution caused by single design of the inlet of the cooling channel 1201, effectively prevents local heat accumulation of the fan motor 1112, and improves the cooling efficiency of the fan motor 1112 and the operation safety of the entire electric propulsion system.

[0152] Specifically, in some embodiments of the application described above, it is proposed that the cooling channel 1201 includes a radial inlet 1203 for introducing external airflow. However, in the implementation process, the unreasonable limitation of the position of the radial inlet 1203 leads to increased resistance of airflow entering the cooling channel 1201 and reduced flow efficiency, thereby affecting the heat dissipation effect of the fan motor 1112 and possibly causing overheating failure of the fan motor 1112.

[0153] To this end, the application further proposes that the radial inlet 1203 is arranged at one end of the outer peripheral side wall of the fan motor 1112 close to the axial inlet 1202. The radial inlet 1203 refers to an opening structure arranged on the outer peripheral side wall of the fan motor 1112 for introducing external airflow, which can be implemented in the form of a single opening or multiple openings, aiming to provide diversified airflow introduction path selection. The radial inlet 1203 is arranged at one end of the outer peripheral side wall of the fan motor 1112 close to the axial inlet 1202, which means that the position is located in the end region of the outer peripheral side wall of the fan motor 1112 and adjacent to the axial inlet 1202. It can be understood that the radial inlet 1203 is arranged close to the axial inlet 1202 in the axial direction of the outer peripheral side wall of the fan motor 1112, aiming to shorten the flow distance of airflow from the mounting interval to the radial inlet 1203 and reduce energy loss.

[0154] Specifically, since the radial inlet 1203 is configured at one end of the circumferential side wall of the fan motor 1112 close to the axial inlet 1202, after passing through the installation interval, the external airflow can enter the cooling channel 1201 from the axial inlet 1202 and the radial inlet 1203 at the same time with a shorter path, which reduces the diffusion and turning of the airflow and reduces the flow resistance. At the same time, the airflow path of the axial inlet 1202 and the radial inlet 1203 is highly coordinated, avoiding flow separation or vortex phenomenon caused by too far apart, thereby enhancing the continuity and stability of the airflow, and effectively improving the heat carrying efficiency of the cooling channel 1201 to the fan motor 1112.

[0155] Through the above scheme, the resistance of the airflow entering the cooling channel 1201 is effectively reduced, the flow efficiency is improved, thereby enhancing the heat dissipation effect of the fan motor 1112, and avoiding overheating failure of the fan motor 1112 caused by poor heat dissipation.

[0156] Specifically, in some embodiments of the present application, the inlet and outlet of the cooling channel 1201 are designed to guide the airflow to dissipate heat from the fan motor 1112, however, during implementation, the airflow is prone to sudden flow rate drop or flow resistance when passing through the cooling channel 1201, resulting in reduced heat dissipation efficiency, difficulty in timely dissipation of heat from the fan motor 1112, and further causing overheating failure risk.

[0157] To this end, the present application further proposes that the sum of the total flow area of the axial inlet 1202 and the total flow area of the radial inlet 1203 is greater than or equal to the total flow area of the axial outlet 1204. In actual application, the total flow area of the axial inlet 1202 refers to the sum of the flow areas of all axial inlets 1202, which can be realized by circular holes, rectangular slots or other arbitrary shaped inlets, the purpose being to ensure sufficient airflow from the axial end face of the fan motor 1112 into the cooling channel 1201. The total flow area of the radial inlet 1203 refers to the sum of the flow areas of all radial inlets 1203, which can be realized by slots or holes arranged along the circumferential side wall of the fan motor 1112, the purpose being to integrate multi-directional air intake capability to improve airflow convergence efficiency. The total flow area of the axial outlet 1204 refers to the sum of the flow areas of all axial outlets 1204, which can be realized by holes or slots at corresponding positions of the axial inlet 1202, the purpose being to guide the airflow to flow stably to the radiator 1113. These designs lay a foundation for optimizing the airflow dynamics characteristics by reasonably configuring the relative relationship of the flow areas.

[0158] Specifically, the scheme of the present application sets the sum of the total flow areas of the axial inlet 1202 and the radial inlet 1203 to be greater than or equal to the total flow area of the axial outlet 1204, based on the principle of airflow continuity, so that the airflow maintains a uniform and stable flow rate when passing through the cooling channel 1201. This area matching relationship prevents the intake resistance caused by insufficient area at the inlet, while avoiding the flow rate decay and airflow diffusion phenomenon caused by the sudden increase of area at the outlet, thereby ensuring that the airflow can continuously and efficiently carry heat through the radiator 1113, and strengthening the heat exchange process.

[0159] As a preferred embodiment, the scheme of the present application is implemented as follows: the axial inlet 1202 can be set as four uniformly distributed circular holes, the radial inlet 1203 can be set as eight rectangular slots spaced along the circumference of the fan motor 1112, and the axial outlet 1204 can be set as four circular holes corresponding to the axial inlet 1202. In this configuration, the sum of the total flow areas of the axial inlet 1202 and the radial inlet 1203 is slightly greater than the total flow area of the axial outlet 1204 to meet the airflow continuity requirement.

[0160] Through the above scheme, the airflow in the cooling channel 1201 is less likely to experience a sudden drop in flow rate or flow resistance, and the heat dissipation efficiency is improved, so that the heat of the fan motor 1112 can be dissipated in time, thereby reducing the risk of overheating failure.

[0161] However, in this process, since the inlet and outlet can be single designed, the airflow distribution is uneven, which leads to insufficient cooling in the local area of the fan motor 1112 and generates hot spot risk, affecting the heat dissipation performance and safe operation of the fan motor 1112.

[0162] To this end, the present application further proposes that a plurality of axial inlets 1202 are arranged at intervals (uniformly or non-uniformly) around the axis of the fan motor 1112, a plurality of radial inlets 1203 are arranged at intervals (uniformly or non-uniformly) along the circumference of the fan motor 1112, and a plurality of axial outlets 1204 are arranged at intervals (uniformly or non-uniformly) around the axis of the fan motor 1112. Among them, the plurality of axial inlets 1202 refers to a plurality of openings arranged on the axial end face of the fan motor 1112, which can be realized by uniformly distributed circular holes or slit structures, aiming to make the airflow evenly dispersed in the circumferential direction when entering from the installation interval, avoiding the airflow concentration phenomenon caused by a single inlet. The plurality of radial inlets 1203 can be understood as a plurality of openings arranged on the outer peripheral side wall of the fan motor 1112, which can be realized by equidistantly distributed rectangular grooves or arc grooves in the circumferential direction, aiming to allow external airflow to flow into the cooling channel 1201 from different angles simultaneously, enhancing the airflow penetration ability in the radial direction. The plurality of axial outlets 1204 refers to a plurality of openings arranged on the axial end face of the fan motor 1112 close to the radiator 1113, which can be realized by circular holes or annular grooves, aiming to make the cooled airflow evenly discharged from multiple points, preventing airflow congestion at the outlet.

[0163] Specifically, the interval arrangement of the plurality of axial inlets 1202 ensures the uniform entry of airflow in the axial direction, the circumferential arrangement of the plurality of radial inlets 1203 enhances the multi-angle inflow ability of airflow from the external environment, and the arrangement of the plurality of axial outlets 1204 ensures the uniform distribution of airflow when discharging. This multi-point distribution design enables the airflow in the cooling channel 1201 to flow evenly through each area of the fan motor 1112, effectively eliminating cooling dead angles and improving overall cooling efficiency.

[0164] Specifically, in some embodiments of the present application described above, the cooling fan 1114 is used to guide the airflow through the radiator 1113. However, in this process, the cooling fan 1114 hinders the airflow flowing out of the axial outlet 1204 of the fan motor 1112, resulting in uneven airflow distribution and flow obstruction, thereby reducing the cooling efficiency and affecting the cooling performance of the entire electric propulsion system.

[0165] To this end, as shown in FIG. 12, the present application proposes that the plurality of axial inlets 1202 are arranged at intervals (uniformly or non-uniformly) around the axis of the fan motor 1112, the plurality of radial inlets 1203 are arranged at intervals (uniformly or non-uniformly) along the circumference of the fan motor 1112, and the plurality of axial outlets 1204 are arranged at intervals (uniformly or non-uniformly) around the axis of the fan motor 1112. Figures 17-18As shown, the application further proposes that the heat dissipation fan 1114 includes a center support 1401, fan blades 1403, and a wind guard ring 1404, the wind guard ring 1404 is sleeved on the outer circumferential side of the center support 1401 and is arranged in a spaced manner with the center support 1401, one end of the fan blade 1403 is connected to the center support 1401, and the other end is connected to the wind guard ring 1404, the number of fan blades 1403 is multiple, which can be any value between 3 and 20, or other values, which are not listed one by one here. Moreover, the center support 1401 is provided with a through hole 1402, which communicates the axial outlet 1204 and the area of the heat dissipation fan 1114 facing the radiator 1113.

[0166] Among them, the center support 1401 refers to the core structural component supporting the heat dissipation fan 1114, which can be made of metal alloy or high-strength composite material, used to provide mechanical strength and stability. The fan blade 1403 refers to a rotating blade that generates airflow power, which can be implemented by a lightweight material with an airfoil cross-section design to optimize airflow guiding efficiency. The wind guard ring 1404 refers to a ring structure surrounding the center support 1401, which can be made of rigid plastic or metal sheet, forming an airflow passage by maintaining a fixed gap with the center support 1401. The through hole 1402 refers to the air hole on the center support 1401, which can be implemented by a circular, elliptical or polygonal hole array, the purpose of which is to eliminate the blocking effect of the solid structure on the airflow, ensuring continuous airflow.

[0167] Specifically, the scheme of the application directly communicates the axial outlet 1204 of the fan motor 1112 through the through hole 1402 of the center support 1401, so that the airflow can smoothly pass through the center support 1401 area without detouring. At the same time, the ring-shaped airflow passage is formed by the spaced arrangement between the wind guard ring 1404 and the center support 1401, guiding the airflow to diffuse uniformly in the circumferential direction. The structure that one end of the fan blade 1403 is connected to the center support 1401 and the other end is connected to the wind guard ring 1404 makes the airflow efficiently pushed from the center area to the periphery when rotating, combined with the flow guiding effect of the wind guard ring 1404, the airflow is stably covered to the surface of the radiator 1113. The above-mentioned structure cooperates to effectively avoid airflow concentration or local turbulence, ensuring the uniformity of airflow distribution and the stability of speed.

[0168] As a preferred embodiment, the scheme of the application is implemented as follows: the center support 1401 is made of aluminum alloy material, and a plurality of circular through holes 1402 are uniformly distributed on the surface. The wind guard ring 1404 is made of engineering plastic by injection molding, and is sleeved on the outer circumferential side of the center support 1401 and maintains a uniform gap. The fan blade 1403 is made of carbon fiber composite material, one end is fixed to the center support 1401 by bolts, and the other end is embedded in the clamping groove on the inner side of the wind guard ring 1404, ensuring that the airflow flows along the designed path when rotating.

[0169] Through the above scheme, the airflow can directly pass through the center support 1401 from the axial outlet 1204 of the fan motor 1112 through the through hole 1402, airflow resistance caused by flow resistance is avoided, airflow distribution is more uniform and flow path is continuous, and therefore heat exchange efficiency of the radiator 1113 is significantly improved, and the thermal management reliability of the electric propulsion system in a continuous working state is effectively ensured.

[0170] In actual application, in some embodiments of the present application, the center support 1401 is provided with the through hole 1402 for communicating the axial outlet 1204. However, in the implementation process, when the axial outlet 1204 is multiple, a single through hole 1402 is difficult to match the distribution of multiple outlets, resulting in congestion of airflow when passing through the center support 1401, uneven distribution of cooling airflow, and reduced cooling efficiency in local areas, thereby affecting the overall cooling performance.

[0171] To this end, the present application further provides that the number of through holes 1402 is multiple, which can be any value between 3 and 30, or other values, which are not listed here. In addition, the through hole 1402 and the axial outlet 1204 are one-to-one corresponding.

[0172] In actual application, the multiple through holes 1402 mean that multiple independent holes are provided on the center support 1401, which can be implemented by using circular, elliptical or rectangular holes, etc. The purpose is to disperse the airflow path and avoid congestion of airflow at a single channel. The one-to-one corresponding of the through hole 1402 and the axial outlet 1204 can be understood as that each through hole 1402 establishes an accurate position matching relationship with an axial outlet 1204, which can be implemented by using coordinate positioning or template alignment based on the arrangement of the axial outlet 1204. The purpose is to ensure that the airflow flows into the corresponding through hole 1402 independently from each axial outlet 1204, and prevent airflow interference.

[0173] Specifically, the scheme of the present application realizes uniform distribution and stable flow of airflow by one-to-one corresponding of multiple through holes 1402 and multiple axial outlets 1204, so as to improve the overall flow capacity. In addition, the design of multiple through holes 1402 can reduce the weight of the center support 1401, which is conducive to the lightweight design of the entire aircraft.

[0174] As a preferred embodiment, the scheme of the present application is implemented as follows: the center support 1401 is made of aluminum alloy material, and is provided with four circular through holes 1402 which are uniformly distributed around the axis of the center support 1401, and the position of each through hole 1402 is accurately corresponding to the position of the axial outlet 1204 of the fan motor 1112, so that the airflow can smoothly flow from the axial outlet 1204 into the through hole 1402.

[0175] Through the above scheme, the present application effectively avoids the concentration of airflow at the center support 1401, ensures the uniform distribution of the cooling airflow, improves the heat dissipation efficiency of the local area, and thus enhances the overall cooling performance.

[0176] Specifically, in some embodiments of the present application, the through hole 1402 is provided to communicate the airflow, however, during the implementation process, the flow area mismatch or position deviation of the through hole 1402 and the axial outlet 1204 will cause airflow obstruction, increased turbulence and airflow leakage, resulting in reduced heat dissipation efficiency, and thus affecting the timely cooling of the fan motor 1112 and the motor 1111, threatening the flight safety.

[0177] To this end, the present application further provides that the flow area of the through hole 1402 is greater than or equal to the flow area of the axial outlet 1204, and the orthographic projection of each through hole 1402 on the axial end face of the fan motor 1112 completely covers the corresponding axial outlet 1204. Wherein, the flow area of the through hole 1402 refers to the effective cross-sectional area of the through hole 1402, which can be realized by a circular, elliptical or polygonal hole, aiming to avoid the sudden increase of velocity and pressure loss caused by the sudden reduction of cross section after the airflow flows out of the axial outlet 1204. The orthographic projection completely covers can be understood as that the projection area of the through hole 1402 on the axial end face completely contains the outline of the axial outlet 1204, which can be realized by a concentric arrangement or an accurately aligned hole design, aiming to ensure that all the airflow flowing out of the axial outlet 1204 enters the through hole 1402 without leakage, eliminating the airflow bypass phenomenon.

[0178] Specifically, the scheme of the present application realizes the smooth transition and non-leakage transmission of the airflow between the fan motor 1112 and the cooling fan 1114 by making the flow area of the through hole 1402 not less than the flow area of the axial outlet 1204, and ensuring that the orthographic projection of the through hole 1402 completely covers the axial outlet 1204. Since the airflow directly enters the through hole 1402 after flowing out of the axial outlet 1204, the sudden change of flow cross section is avoided, so that the stable flow state of the airflow is maintained. At the same time, the accurate covering design of the through hole 1402 eliminates the airflow bypass path, so that the heat can be continuously and uniformly carried away, preventing local heat accumulation.

[0179] As a specific embodiment, the through hole 1402 of the center support 1401 is designed as a plurality of circular holes, the diameter of which is slightly larger than the diameter of the axial outlet 1204, and the hole position is accurately aligned with the position of the axial outlet 1204, so as to ensure smooth airflow through the center support 1401 of the cooling fan 1114.

[0180] Through the above scheme, the application effectively avoids airflow obstruction, increased turbulence and airflow leakage, improves the overall performance of the cooling system, ensures timely cooling of the fan motor 1112 and the power motor 1111 under high load conditions, and guarantees flight safety.

[0181] As a key power component, the electric propulsion system of the fixed rotor inevitably generates a large amount of heat energy during operation, and must rely on the cooling system to achieve efficient heat dissipation to maintain system stability. The core component of the cooling system, the radiator, continuously exports heat through the heat exchange process between external airflow and the heat dissipation surface, thereby guaranteeing the normal working temperature range of the electric propulsion system. If the heat dissipation mechanism cannot timely and effectively transfer heat, it will cause system overheating failure, and in severe cases, power failure, directly endangering the safety of the aircraft structure and the lives of personnel. Therefore, the reasonable design of the airflow introduction path, the optimization of the internal flow characteristics of the radiator, and the improvement of the airflow exhaust efficiency are the key determinants of the performance of the cooling system.

[0182] To this end, as shown in Figures 19-21 , the application provides an electric propulsion cooling system 110 further comprising a fan frame 1115 in a cover structure, one end (close to the center end) of the fan frame 1115 is sleeved on the outer circumferential side of the fan motor 1112 body, the other end (close to the edge end) extends away from the power motor 1111 and is sleeved on the outer circumferential side of the cooling fan 1114, the fan frame 1115 can play multiple roles such as isolating the cooling fan 1114 and the power motor 1111, and protecting the cooling fan 1114.

[0183] The fan motor 1112 is arranged on the side of the power motor 1111 away from the propeller 112. In actual application, the fan motor 1112 is arranged at the axial rear end of the power motor 1111, which can be directly fixed on the shell of the power motor 1111 or installed through an independent support, for example, the fan motor 1112 is coaxially arranged with the power motor 1111 but spaced a certain distance, or the fan motor 1112 is installed on the rear end face of the power motor 1111 through a flange connector, which mainly realizes effective isolation of the airflow between the fan motor 1112 and the propeller 112 and reduces the running vibration. Further, the radiator 1113 is arranged on the side of the cooling fan 1114 away from the power motor 1111. Specifically, the radiator 1113 is arranged in the downstream direction of the airflow of the cooling fan 1114, which can be supported by a support at the outlet of the cooling fan 1114 or fixed through a suspension structure, for example, the radiator 1113 is installed behind the cooling fan 1114 using a metal support, or the radiator 1113 is suspended on the extended part of the fan frame 1115 through an elastic connector, which mainly ensures that the airflow directly acts on the surface of the radiator 1113 to improve the heat dissipation efficiency. One end of the fan frame 1115 is sleeved on the outer circumferential side of the fan motor 1112. In actual application, the fan frame 1115 is fixed on the shell of the fan motor 1112 through mechanical connection, which can be realized by bolt fastening or clamp clamping, for example, the fan frame 1115 is clamped on the shell of the fan motor 1112 using a metal clamp, or the fan frame 1115 is press-fitted on the outer circumference of the fan motor 1112, which mainly establishes the stable connection between the fan frame 1115 and the fan motor 1112. Therefore, the end of the fan frame 1115 extending towards the radiator 1113 is covered on the outer circumferential side of the cooling fan 1114. Specifically, the extended cover of the fan frame 1115 forms an annular covering structure to constrain the periphery of the cooling fan 1114, which can be realized by an integrally formed cover structure or a split assembly structure, for example, an integral plastic cover is directly wrapped around the cooling fan 1114 using an injection molding process, or an annular cover is formed by splicing multiple arc-shaped supports, which mainly limits the radial displacement of the cooling fan 1114.

[0184] In actual application, the fan motor 1112 can specifically adopt a permanent magnet synchronous motor, the cooling fan 1114 can specifically be a four-blade axial fan, the fan frame 1115 can be made of aluminum alloy material through precision casting process, and the radiator 1113 can specifically be an array of aluminum radiators. This example integrates the fan motor 1112 and the cooling fan 1114 into a unified support unit through the extended cover structure of the fan frame 1115, which ensures that the cooling fan 1114 maintains a stable trajectory during operation.

[0185] As a preferred embodiment, the extension part of the fan frame 1115 is designed as a continuous annular structure to enhance the overall rigidity. In this way, the fan motor 1112 and the cooling fan 1114 are integrated as a rigid support whole, effectively constraining the movement trajectory of the cooling fan 1114, preventing eccentric displacement during high-speed rotation, thereby avoiding mechanical impact on the radiator 1113 and the power motor 1111, and solving the safety hazard problem caused by eccentricity of the cooling fan 1114.

[0186] Further, the extension cover scheme of the fan frame 1115 strictly limits the movement trajectory of the cooling fan 1114, thereby effectively preventing the eccentricity that may occur during high-speed rotation. In this way, the mechanical impact of the cooling fan 1114 on the radiator 1113 and the power motor 1111 is completely avoided, the running stability of the cooling system is significantly improved, and finally the reliable solution to the safety hazard of the eccentricity of the cooling fan 1114 is realized, ensuring the safe operation of the aircraft.

[0187] Further, the extension cover scheme of the fan frame 1115 constructs an integrated airflow guiding and restraining structure. First, the fan frame 1115 forms a continuous and gradual guide channel at the outer periphery of the cooling fan 1114, which can effectively collect and guide the turbulent airflow on the inlet side and orderly deliver it to the inlet area of the cooling fan 1114. In particular, the fan frame 1115 structure can concentrate part of the airflow to the middle area of the cooling fan 1114, avoiding the problem of insufficient airflow coverage caused by the current design that the airflow only enters along the edge of the cooling fan 1114. In this way, the airflow distribution on the surface of the radiator 1113 is more uniform, and the total amount of airflow passing through the radiator 1113 and the effective contact area per unit time are simultaneously increased, thereby significantly improving the heat exchange efficiency between the radiator 1113 and the air.

[0188] Moreover, the fan frame 1115 plays a role of rectifier, restraining the airflow diffusion of the blade tip of the cooling fan 1114, reducing unnecessary turbulence and flow separation phenomena. The airflow enters the cooling fan 1114 in a smoother manner under the guidance of the fan frame 1115, reducing the aerodynamic noise and flow resistance of the cooling fan 1114 in operation. This not only improves the driving efficiency of the fan motor 1112 and reduces the energy consumption of the cooling system itself, but also provides a stable and controllable flow field environment for the radiator 1113, enabling it to continuously exert the best cooling performance under the design working condition.

[0189] In some embodiments of the application described above, the fan frame 1115 is used to connect the fan motor 1112 and the cooling fan 1114 and guide the airflow, however, in this process, the structural design of the fan frame 1115 may be too simple to effectively prevent the vibration impact caused by eccentricity when the cooling fan 1114 is running, thereby causing damage to the radiator 1113 and the motor 1111, and at the same time, the airflow guide path is not optimized, affecting the cooling efficiency and threatening flight safety.

[0190] To this end, the fan frame 1115 includes a guide vane 1501, an inner ring support 1502 and an outer ring support 1503, the outer ring support 1503 and the inner ring support 1502 are coaxially arranged, the inner diameter of the outer ring support 1503 is greater than the outer diameter of the inner ring support 1502, one end of the guide vane 1501 is connected to the outer circumferential side of the inner ring support 1502, and the other end is connected to the outer ring support 1503, and the fan frame 1115 is sleeved on the outer circumferential side of the fan motor 1112 through the inner ring support 1502.

[0191] In practical applications, the guide vane 1501 refers to a structural component for guiding airflow, which can be realized by adopting an arc-shaped plate structure or a blade with a specific curvature, and its purpose is to optimize the airflow path and reduce turbulence. The inner ring support 1502 refers to a support structure located on the inner side of the fan frame 1115, which can be made of a ring-shaped metal frame or a composite material, and its purpose is to provide a connection point with the fan motor 1112 and enhance structural stability. Specifically, the outer ring support 1503 refers to a support structure located on the outer side of the fan frame 1115, which can adopt a larger diameter ring-shaped support, and its purpose is to accommodate the guide vane 1501 and connect the cooling fan 1114 area. In practical applications, coaxial arrangement means that the inner ring support 1502 and the outer ring support 1503 share the same center axis, which can be precisely machined to ensure concentricity, and its purpose is to avoid vibration accumulation. The inner diameter of the outer ring support 1503 is greater than the outer diameter of the inner ring support 1502, which refers to the size fitting relationship, which can be realized by adopting clearance fitting or transition fitting, and its purpose is to allow small displacement caused by thermal expansion or manufacturing tolerance. Specifically, one end of the guide vane 1501 is connected to the outer circumferential side of the inner ring support 1502, and the other end is directly or indirectly connected to the outer ring support 1503, which refers to the connection method, which can be realized by welding, bolt connection or integral molding, and its purpose is to build a continuous airflow channel. In practical applications, the fan frame 1115 is sleeved on the outer circumferential side of the fan motor 1112 through the inner ring support 1502, which refers to the installation method, which can be realized by adopting interference fit or elastic buckle, and its purpose is to realize structural integration and disperse centrifugal force.

[0192] Specifically, the scheme of the application ensures that the fan frame 1115 maintains strict concentricity during assembly and operation through the coaxial arrangement of the outer ring support 1503 and the inner ring support 1502, avoids vibration accumulation caused by axis deviation, and thus suppresses the occurrence of eccentricity of the cooling fan 1114. The inner diameter of the outer ring support 1503 is larger than the outer diameter of the inner ring support 1502 to form a precise size fitting gap, so that the inner ring support 1502 can be reliably sleeved on the outer peripheral side of the fan motor 1112, accommodating the slight displacement caused by thermal expansion or manufacturing tolerance, and preventing mechanical jamming during operation. The guide vane 1501 is connected to the outer peripheral side of the inner ring support 1502 at one end and connected to the outer ring support 1503 at the other end to construct a continuous airflow guide path, which naturally forms a converging channel from the outer ring to the inner ring according to the geometric layout of the support, guides the airflow to flow through the radiator 1113 in the preset direction efficiently, and avoids the blind area caused by airflow turbulence. The fan frame 1115 is sleeved on the outer peripheral side of the fan motor 1112 through the inner ring support 1502 to realize integrated installation, and the close fit of the inner ring support 1502 and the outer peripheral side of the fan motor 1112 enhances the rigid support of the overall frame and effectively disperses the centrifugal force when the cooling fan 1114 rotates, thereby fundamentally reducing the risk of impact.

[0193] As a specific implementation, the scheme of the application is implemented as follows: the inner ring support 1502 of the fan frame 1115 adopts a ring structure, the outer ring support 1503 adopts a larger diameter metal ring, the guide vane 1501 is composed of multiple aluminum arc-shaped blades, one end is welded to the outer peripheral side of the inner ring support 1502, and the other end is fixed to the outer ring support 1503 through the connecting support 1504, wherein the connecting support 1504 is distributed along the circumference of the outer ring support 1503, and the fan frame 1115 is sleeved on the outer peripheral side of the fan motor 1112 through the inner ring support 1502 to form stable support.

[0194] Through the above scheme, the structural stability of the fan frame 1115 is significantly improved, the vibration impact caused by eccentricity during fan operation is effectively prevented, the damage to the radiator 1113 and the power motor 1111 is avoided, the service life is improved, and the airflow guide path is optimized to improve the cooling efficiency.

[0195] Specifically, in some embodiments of the application described above, the inner ring support 1502 and the outer ring support 1503 are coaxially arranged to support the guide vane 1501. However, during implementation, the non-uniform flow and vortex phenomenon occur when the airflow passes through the guide vane 1501 due to the coaxial arrangement, which not only reduces the cooling efficiency, but also makes the cooling fan 1114 prone to direct impact on the radiator 1113 and the power motor 1111 when it is eccentric, thereby causing unstable operation of the power device and threatening flight safety.

[0196] To this end, the inner ring support 1502 and the outer ring support 1503 are arranged axially offset, and the inner ring support 1502 is arranged on the side of the outer ring support 1503 away from the cooling fan 1114. Of course, in other embodiments, the inner ring support 1502 and the outer ring support 1503 can also be arranged axially coincident.

[0197] Specifically, the axial offset arrangement of the inner ring support 1502 and the outer ring support 1503 means that the inner ring support 1502 and the outer ring support 1503 are not in the same plane in the axial direction of the fan frame 1115, but are arranged axially offset. This can be achieved by directly offset forming the support body or by offsetting through detachable connecting pieces. The purpose is to avoid turbulence and vortex of airflow when passing through the guide vane 1501 due to sudden change of cross section, thereby improving the uniformity of airflow. Wherein, the inner ring support 1502 is arranged on the side of the outer ring support 1503 away from the cooling fan 1114, which means that the inner ring support 1502 is located at the axial end of the outer ring support 1503, and the end is away from the cooling fan 1114. It can be understood that the inner ring support 1502 is offset relative to the outer ring support 1503 towards the direction close to the motor 1111, thereby providing sufficient guiding space for airflow. The purpose is to strengthen the guiding effect of the guide vane 1501 on the airflow, and to ensure that the airflow flows to the radiator 1113 in a concentrated and efficient manner.

[0198] In actual application, in some embodiments of the application described above, the inner ring support 1502 and the outer ring support 1503 are arranged axially offset to optimize the airflow guiding path. However, in the implementation process, since the inner ring support 1502 is arranged on the side of the outer ring support 1503 away from the cooling fan 1114, the connection of the guide vane 1501 and the outer ring support 1503 is difficult to achieve directly due to the axial offset, resulting in that the connection structure is prone to vibration and eccentricity when the cooling fan 1114 rotates at high speed, thereby causing impact on the radiator 1113 and the motor 1111, affecting the cooling efficiency and threatening the flight safety.

[0199] To this end, the inner ring support 1502 and the outer ring support 1503 are arranged axially offset, and the inner ring support 1502 is arranged on the side of the outer ring support 1503 away from the cooling fan 1114. Of course, in other embodiments, the inner ring support 1502 and the outer ring support 1503 can also be arranged axially coincident.

[0200] The connecting bracket 1504 is a transition structure for connecting the guide vane 1501 and the outer ring bracket 1503, which can be implemented by an independent metal bracket or a composite material bracket, and its purpose is to provide a stable connection point to adapt to the axial misalignment. One end of the connecting bracket 1504 is connected to the axial side end face of the outer ring bracket 1503, which can be understood as using the flat area of the end face as a connection base point to avoid the stress concentration problem that may be caused by connecting on the side face of the bracket, and its purpose is to provide a stable support foundation for the entire structure. The other end of the connecting bracket 1504 is protruding along the axial direction of the outer ring bracket 1503, which means that the protruding direction is consistent with the axial direction, and it can be implemented by a straight rod or a curved structure, and its purpose is to accurately adapt to the axial misalignment distance between the inner ring bracket 1502 and the outer ring bracket 1503. The other end of the guide vane 1501 is connected to the end of the connecting bracket 1504 away from the outer ring bracket 1503, which means that the connection point is located at the end of the connecting bracket 1504, and it can be implemented by bolt connection or welding, and its purpose is to make the stress distribution of the guide vane 1501 more uniform and reduce the vibration amplitude during high-speed rotation.

[0201] Specifically, in the scheme of the present application, one end of the connecting bracket 1504 is fixed to the axial end face of the outer ring bracket 1503, and the flatness of the end face is used to provide stable connection. The other end of the connecting bracket 1504 protrudes and extends along the axial direction, and accurately matches the axial misalignment distance between the inner ring bracket 1502 and the outer ring bracket 1503. One end of the guide vane 1501 is connected to the outer peripheral side of the inner ring bracket 1502, and the other end is connected to the end of the connecting bracket 1504, so that the guide vane 1501 can realize smooth transition without additional bending during connection, and the stress distribution is uniform, thereby significantly reducing the vibration and deviation risk of the cooling fan 1114 during high-speed rotation, and preventing the impact of the eccentric cooling fan 1114 on the cooling system. Moreover, and most importantly, by setting the connecting bracket 1504, the side part (outer peripheral side direction) of the fan frame 1115 can also intake air, thereby greatly improving the air intake range of the fan frame 1115, which is conducive to the cooling of the entire electric motor 111.

[0202] Specifically, in some embodiments of the present application, the fan frame 1115 is sleeved on the outer peripheral side of the fan motor 1112. However, during this process, the vibration or eccentricity of the fan motor 1112 may cause impact on the radiator 1113 and the motor 1111, thereby threatening the flight safety of the electric propulsion system.

[0203] To this end, the present application further provides that the fan frame 1115 is installed on the arm 113, and the inner diameter of the inner ring bracket 1502 is greater than the outer diameter of the fan motor 1112, so that the inner ring bracket 1502 and the fan motor 1112 are gap-fitted.

[0204] The gap fit refers to a reserved gap between the fan frame 1115 and the fan motor 1112, which can be achieved by machining tolerance control or assembly gap design. Specifically, an appropriate tolerance band can be set between the inner diameter of the fan frame 1115 and the outer diameter of the fan motor 1112, which aims to allow the fan motor 1112 to have a small degree of freedom during operation to absorb vibration and eccentric displacement. The gap fit can also be achieved by an elastic bushing or a floating installation structure, which aims to avoid stress concentration caused by direct rigid contact.

[0205] Specifically, the scheme of the present application sets a gap fit between the fan frame 1115 and the fan motor 1112, so that when the fan motor 1112 rotates at high speed and slight vibration or eccentric displacement occurs, the gap can accommodate and buffer the displacement, preventing the fan frame 1115 and the fan motor 1112 from producing direct friction or mechanical impact, thereby blocking the transmission path of the impact force to the radiator 1113 and the power motor 1111, and ensuring the structural integrity of the electric propulsion system under dynamic working conditions.

[0206] In actual application, in some embodiments of the above-mentioned scheme of the present application, the guide vane 1501 is used to guide the airflow through the radiator 1113 for heat dissipation. However, in the implementation process, a single guide vane 1501 can cause uneven airflow distribution, local overheating areas on the surface of the radiator 1113, and reduced cooling efficiency. At the same time, airflow turbulence can exacerbate the vibration of the cooling fan 1114, increase the risk of eccentricity, and threaten flight safety.

[0207] To this end, the present application further provides that the number of guide vanes 1501 is multiple, and the guide vanes 1501 and the connecting brackets 1504 are one-to-one corresponding. The multiple connecting brackets 1504 are uniformly and interval distributed along the circumferential direction of the outer ring bracket 1503. However, it should be noted that in order to prevent interference with the installation of the fan frame 1115, the spacing between some guide vanes 1501 is large. At this time, in order to ensure the connection strength, the adjacent guide vane 1501 brackets are provided with a reinforcing cross bar 1505 extending along the circumferential direction.

[0208] The plurality of guide vanes 1501 are arranged in a plurality of sets, which can be implemented by several sets, and the purpose is to disperse the airflow to avoid local overheating caused by concentrated flow. The one-to-one correspondence between the guide vanes 1501 and the connecting brackets 1504 can be understood as each guide vane 1501 being provided with an independent connecting bracket 1504 for support, which can be implemented by welding, bolt connection or buckle connection, etc. The purpose is to ensure the positioning accuracy of each guide vane 1501 and prevent vibration deviation. The plurality of connecting brackets 1504 are distributed along the circumferential direction of the outer ring bracket 1503, which means that the connecting brackets 1504 are distributed on the circumference, which can be implemented by arranging different intervals, and the purpose is to balance the airflow pressure and reduce vortex formation.

[0209] Specifically, the scheme of the present application disperses the airflow to the surface of the radiator 1113 by arranging a plurality of guide vanes 1501 and optimizing the layout structure, avoiding local overheating caused by single-point concentration. The one-to-one correspondence between the guide vanes 1501 and the connecting brackets 1504 maintains the stability of the airflow channel and reduces energy loss. The interval distribution of the plurality of connecting brackets 1504 along the circumferential direction of the outer ring bracket 1503 balances the airflow inlet pressure by symmetry, prevents airflow deflection, and thus improves the overall cooling efficiency and system reliability.

[0210] As a specific implementation, the scheme of the present application is implemented as follows: the guide vanes 1501 can be arranged in a plurality of sets, the connecting brackets 1504 are distributed along the circumferential direction of the outer ring bracket 1503 and are fixed to the end face of the outer ring bracket 1503 by standard connecting pieces, and the guide vanes 1501 are designed in an arc cross-section to form an airflow groove 1506, so that the airflow can smoothly flow into the radiator 1113.

[0211] Through the above scheme, the airflow distribution on the surface of the radiator 1113 is more uniform, effectively eliminating the local overheating area and improving the cooling efficiency. At the same time, the smooth flow of the airflow reduces the vibration of the cooling fan 1114 and reduces the risk of eccentricity, thereby ensuring the safe operation of the aircraft.

[0212] In actual application, in some embodiments of the present application, the fan frame 1115 includes the structure of the guide vanes 1501, the inner ring bracket 1502, the outer ring bracket 1503 and the connecting bracket 1504 to guide the airflow and support the cooling system. However, during implementation, these components are prone to loose connection due to manufacturing tolerance or assembly gap when the cooling fan 1114 is running at high speed, causing structural vibration and geometric deformation, which in turn causes the risk of eccentricity of the cooling fan 1114. Not only does it weaken the airflow guiding effect and affect the cooling efficiency, but it also may impact the radiator 1113 and the power motor 1111, threatening flight safety.

[0213] To this end, the application further proposes that the guide vane 1501, the inner ring support 1502, the outer ring support 1503 and the connecting support 1504 are integrally formed. The integrally formed refers to integrating multiple structural components into an indivisible whole structure through a single manufacturing process, which can be realized by processes such as metal die casting, powder metallurgy sintering or polymer material injection molding, etc. The purpose is to completely eliminate the assembly interface between the split components, avoid the connection loosening problem caused by long-term vibration or manufacturing tolerance accumulation, and thus ensure the structural integrity of the fan frame 1115 under dynamic working conditions.

[0214] But not limited to this, in other embodiments, the guide vane 1501, the inner ring support 1502, the outer ring support 1503 and the connecting support 1504 can also be adhesively, clamped or welded, which are not listed one by one here.

[0215] In actual application, in some embodiments of the application described above, if the guide vane 1501 adopts a straight line or other non-optimized cross-sectional shape, it will cause turbulent vortex when the airflow passes through the guide vane 1501, increase the flow resistance, reduce the heat dissipation efficiency, and thus affect the stable operation of the electric propulsion system.

[0216] To this end, the application further proposes that the cross section of the guide vane 1501 along the axial direction of the inner ring support 1502 is arc-shaped (including but not limited to circular arc, elliptical arc or other arc line shape, etc., which are not listed one by one here).

[0217] Specifically, the cross section of the guide vane 1501 along the axial direction of the inner ring support 1502 is arc-shaped, which means that the cross section shape is a continuous curved line, which can be realized by generalized curved surface shapes such as parabolic, elliptical or circular arc, etc. The purpose is to reduce the separation and turbulence of the airflow on the surface of the guide vane 1501, and ensure smooth transition of the airflow. The airflow groove 1506 refers to the channel formed by one side of the guide vane 1501, which can be designed as a straight line, a tapered or an expanding type, etc. The purpose is to concentrate and guide the airflow to pass through the radiator 1113 efficiently, and to strengthen the heat exchange.

[0218] Specifically, the scheme of the application realizes continuous and smooth curved surface transition of the airflow when flowing in the radial direction through the arc-shaped cross section of the guide vane 1501, avoiding sudden turning or separation of the airflow on the surface of the guide vane 1501. At the same time, the extension direction of the airflow groove 1506 is consistent with the natural flow trend of the airflow from outside to inside, concentrating and guiding the airflow to pass through the radiator 1113 efficiently, thereby strengthening the heat exchange process, and finally realizing more reliable and efficient heat dissipation management of the power motor 1111.

[0219] As a specific implementation, the scheme of the application is implemented as follows: the flow guide piece 1501 is made of aluminum alloy material, and the cross-sectional shape is circular arc. The inlet width of the air flow groove 1506 is slightly larger than the outlet width to meet the air flow acceleration requirement. In addition, the surface of the flow guide piece 1501 is coated with a low-friction coating to further reduce air flow resistance.

[0220] Through the above scheme, the application effectively reduces the turbulent vortex of air flow on the surface of the flow guide piece 1501, reduces the flow resistance, improves the heat dissipation efficiency, and thus guarantees the stable operation of the electric propulsion system.

[0221] However, it is not limited to this, and in other embodiments, the flow guide piece 1501 can also be a planar plate structure.

[0222] Specifically, in some embodiments of the application described above, the air flow groove 1506 is used to guide the air flow from the outer ring support 1503 to the inner ring support 1502. However, during implementation, if the distribution directions of the plurality of air flow grooves 1506 are inconsistent, it will cause air flow interference, generate turbulent flow, and reduce the heat dissipation efficiency.

[0223] To this end, the application further proposes that the plurality of air flow grooves 1506 are distributed on one side of the corresponding flow guide piece 1501 along the same rotation direction. The air flow groove 1506 is a groove structure formed on the flow guide piece 1501 for guiding air flow, which can be realized by adopting an arc cross-section design. The same rotation direction means that the distribution directions of all air flow grooves 1506 are consistent, which can be realized by adopting clockwise or counterclockwise distribution matching the rotation direction of the cooling fan 1114. The purpose is to ensure the uniformity of the air flow direction and avoid air flow collision caused by direction difference.

[0224] Specifically, the scheme of the application guides the air flow to maintain a consistent flow direction when passing through the flow guide piece 1501 by distributing the plurality of air flow grooves 1506 along the same rotation direction. The direction matches the rotation direction of the cooling fan 1114, thereby avoiding air flow collision and vortex formation caused by inconsistent directions, reducing flow resistance, ensuring efficient air flow through the surface of the radiator 1113, and enhancing heat exchange effect.

[0225] As a specific implementation, the scheme of the application is implemented as follows: the air flow grooves 1506 of the flow guide piece 1501 are designed to be distributed in the clockwise direction. When the fan motor 1112 drives the cooling fan 1114 to rotate clockwise, the air flow is guided to flow in the same direction, reducing vortex formation.

[0226] However, it is not limited to this, and in other embodiments, part of the air flow grooves 1506 are distributed in the counterclockwise direction, and another part of the air flow grooves 1506 are distributed in the clockwise direction.

[0227] In practical applications, in some embodiments of the application, the air flow groove 1506 is used to guide the air flow from the outer ring support 1503 to the inner ring support 1502, however, in the implementation process, the flow area of the air flow groove 1506 is not reasonably designed, which causes the air flow speed to suddenly change or unevenly distribute in the flow path, which is easy to produce vortex, increase resistance or reduce heat dissipation efficiency, and affects the stability and cooling performance of the heat dissipation system.

[0228] In an embodiment, along the direction from the outer ring support 1503 to the inner ring support 1502, the flow area of the air flow groove 1506 is constant, or the flow area of the air flow groove 1506 is uniformly increasing, or the flow area of the air flow groove 1506 is uniformly decreasing. Among them, the constant flow area means that the cross-sectional area of the air flow groove 1506 remains constant in the flow direction, which can be realized by a straight cylinder channel structure, the purpose of which is to maintain the stability of the air flow speed and avoid energy dissipation and turbulence caused by sudden changes in the cross section. The flow area with a uniform increasing trend means that the cross-sectional area of the air flow groove 1506 increases linearly along the flow direction, which can be realized by a gradually expanding channel structure, the purpose of which is to gradually reduce the air flow speed and prolong the contact time of the air flow with the heat sink 1113. The flow area with a uniform decreasing trend means that the cross-sectional area of the air flow groove 1506 decreases linearly along the flow direction, which can be realized by a gradually tapered channel structure, the purpose of which is to gradually increase the air flow speed and strengthen the scouring effect on the surface of the heat sink 1113.

[0229] Specifically, the scheme of the application effectively optimizes the dynamic characteristics of the heat dissipation air flow by accurately controlling the change mode of the flow area of the air flow groove 1506 in the flow direction. Since the geometric extension direction of the air flow groove 1506 is consistent with the air flow direction, keeping the flow area unchanged can ensure that the air flow passes through the heat dissipation area smoothly and continuously. The flow area with a uniform increasing trend can gradually reduce the air flow speed and enhance the sufficiency of heat exchange. The flow area with a uniform decreasing trend can gradually increase the air flow speed and more efficiently take away the accumulated heat. The flexible selection of these change modes adapts to the heat dissipation needs under different working conditions, based on the regulation of air flow dynamics, reduces the flow resistance and energy loss, thereby forming a complete technical system.

[0230] Through the above technical scheme, the speed distribution of the air flow in the flow path is more uniform, the vortex and resistance are significantly reduced, the heat dissipation efficiency is effectively improved, and the stability and cooling performance of the heat dissipation system are enhanced.

[0231] In general, the scheme of the present application is that the fan frame 1115 is tightly sleeved on the outer circumferential side of the fan motor 1112 at one end, so that the air flow generated when the fan motor 1112 operates is effectively constrained, avoiding the air flow from being scattered in all directions at the source due to no structure guiding, thereby ensuring that the air flow is concentrated to flow to the subsequent components. The other end of the fan frame 1115 extends to cover the outer circumferential side of the cooling fan 1114, creating a continuous and directional channel to guide the air flow to smoothly transition to the area of the cooling fan 1114, reducing turbulence and resistance in the flow process. Among them, the first part of the air flow refers to the air flow path directly transmitted through the internal cooling channel 1201 of the fan motor 1112, which can be understood as continuous heat exchange using the hot air flow generated by the heat dissipation of the fan motor 1112, and the purpose is to avoid the stagnation of heat in the intermediate link. The second part of the air flow refers to the axial air flow path constrained by the fan frame 1115 along the flow direction, which can be specifically a stable flow channel formed inside the frame, and the purpose is to ensure that the air flow efficiently passes through the radiator 1113 with the shortest path. The third part of the air flow refers to the ambient air flow path captured from the gap between the outer circumferential side of the fan frame 1115, which can be manifested as a flow mode of entering radially and then turning axially, and the purpose is to expand the total air flow and optimize the flow direction to adapt to the geometric structure of the radiator 1113.

[0232] Through the above scheme, the present application makes the air flow distribution more uniform and less likely to be lost, and the radiator 1113 can continuously obtain sufficient air flow to cope with the high load heat of the power motor 1111, thereby effectively improving the heat dissipation efficiency and ensuring the safe and stable operation of the electric propulsion system.

[0233] The technical features of the above-mentioned embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described, but as long as the combinations of the technical features do not contradict, they should be considered within the scope of the present application.

[0234] The above-mentioned embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the application. It should be pointed out that for ordinary skilled persons in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the protection scope of the present application. Therefore, the application protection scope of the present application should be subject to the appended claims.

[0235] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship shown in the drawings, which are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0236] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise explicitly specified and limited.

[0237] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "fixing" and the like should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0238] In the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature, which can be direct contact between the first and second features, or indirect contact between the first and second features through intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be directly above or obliquely above the first feature, or only indicate that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature can be directly below or obliquely below the first feature, or only indicate that the horizontal height of the first feature is less than that of the second feature.

[0239] It is to be understood that the terms "fixedly mounted" and "fixedly attached" should be interpreted broadly to include a direct attachment as well as an indirect attachment via one or more intermediary members. It is also to be understood that the terms "connected" and "coupled" broadly refer to both direct connections and indirect connections via one or more intermediary members. The terms "vertical", "horizontal", "upper", "lower", "left", "right", and the like as used herein are made only for purposes of illustration and are not intended to be limiting.

[0240] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

Claims

1. An electric propulsion heat dissipation system, characterized in that, include: Arm (113) is fixedly connected to the fuselage structure of the aircraft, and the arm (113) is provided with an assembly space (1131). An electric motor (111) is installed in the assembly space (1131); and, A propeller (112) is disposed at the output end of the electric motor (111), which is capable of driving the propeller (112) to rotate. The arm (113) has an inlet (1132) on the side surface facing the propeller (112) that communicates with the external space, and the airflow generated when the propeller (112) rotates can at least partially cover the inlet (1132). The arm (113) has an outlet (1135) on the side surface away from the propeller (112) that connects to the external space. The inlet (1132), the assembly space (1131) and the outlet (1135) are connected in sequence. The inlet (1132) includes a first inlet (1133) disposed in the front region of the propeller (112) shaft. The first inlet (1133) is provided with a first grille (114) composed of a plurality of parallel and spaced first guide strips (1141) so that the high-speed airflow generated when the propeller (112) rotates can be directly introduced into the first inlet (1133). The plane where the first inlet (1133) is located has a gradually rising slope structure relative to the horizontal plane. The surface of the first guide strip (1141) facing away from the assembly space (1131) is curved, so that the first guide strip (1141) can stop in the front area of ​​the first inlet (1133) and prevent the airflow in front from entering the assembly space (1131) through the first grille (114).

2. The electric propulsion heat dissipation system according to claim 1, characterized in that, The inlet (1132) also includes a second inlet (1134), and the orthographic projection of the propeller (112) on the corresponding surface of the arm (113) when it rotates at least partially covers one of the first inlet (1133) and the second inlet (1134).

3. The electric propulsion heat dissipation system according to claim 2, characterized in that, The second inlet (1134) is located in the rear region of the propeller (112) shaft.

4. The electric propulsion heat dissipation system according to claim 3, characterized in that, A first guide gap (1142) is formed by spacing between adjacent first guide strips (1141), and the first guide gap (1142) communicates with the assembly space (1131). The second inlet (1134) is provided with a second grille (115), the second grille (115) includes a plurality of parallel second guide strips (1151), and adjacent second guide strips (1151) are spaced apart to form a second guide gap (1152), the second guide gap (1152) is connected to the assembly space (1131).

5. The electric propulsion heat dissipation system according to claim 4, characterized in that, Along the direction from the first inlet (1133) to the second inlet (1134), a plurality of first guide strips (1141) are arranged at intervals, and the length of each first guide strip (1141) tends to increase.

6. The electric propulsion heat dissipation system according to claim 4, characterized in that, The direction of airflow towards the first inlet (1133) when the propeller (112) rotates is defined as the first preset air outlet direction. The airflow along the first preset air outlet direction can directly pass through the first guide gap (1142) and enter the assembly space (1131). The guide direction of the first guide gap (1142) is the same as the first preset air outlet direction.

7. The electric propulsion heat dissipation system according to claim 4, characterized in that, Along the direction from the first inlet (1133) to the second inlet (1134), a plurality of second guide strips (1151) are arranged at intervals, and each second guide strip (1151) has the same length.

8. The electric propulsion heat dissipation system according to claim 4, characterized in that, The direction of airflow towards the second inlet (1134) when the propeller (112) rotates is defined as the second preset air outlet direction. The airflow along the second preset air outlet direction can directly pass through the second guide gap (1152) and enter the assembly space (1131).

9. The electric propulsion heat dissipation system according to claim 8, characterized in that, The second flow guide gap (1152) extends in an arc shape. The flow direction at the opening of the second flow guide gap (1152) near the propeller (112) is the same as the second preset air outlet direction. The flow direction at the opening of the second flow guide gap (1152) near the assembly space (1131) is set vertically downward.

10. The electric propulsion heat dissipation system according to claim 2, characterized in that, The surface where the second inlet (1134) is located has the same shape as the outer contour of the arm (113).

11. The electric propulsion heat dissipation system according to claim 2, characterized in that, The arm (113) is provided with a first flow channel (1136), and the first inlet (1133) is connected to the assembly space (1131) through the first flow channel (1136); along the air intake direction from the first inlet (1133) to the assembly space (1131), the flow area of ​​the first flow channel (1136) tends to increase. And / or, the arm (113) is provided with a second flow channel (1137), and the second inlet (1134) is connected to the assembly space (1131) through the second flow channel (1137); along the air intake direction from the second inlet (1134) to the assembly space (1131), the flow area of ​​the second flow channel (1137) tends to increase.

12. The electric propulsion heat dissipation system according to claim 1, characterized in that, A third grille (116) is provided at the outlet (1135). The third grille (116) includes a plurality of third guide strips (1161) arranged in parallel. Adjacent third guide strips (1161) are spaced apart to form a third guide gap (1162).

13. The electric propulsion heat dissipation system according to claim 12, characterized in that, The third guide strip (1161) is in the shape of a slat, and the guide direction of the third guide gap (1162) is set vertically downward.

14. The electric propulsion heat dissipation system according to claim 1, characterized in that, The electric motor (111) includes: A power motor (1111) is used to drive the propeller (112) to rotate; The radiator (1113) is capable of dissipating heat from the power motor (1111) through coolant circulation; A cooling fan (1114) is disposed between the power motor (1111) and the radiator (1113); A fan motor (1112) is used to drive the cooling fan (1114) to rotate; and, The fan frame (1115) is fitted at one end to the outer periphery of the fan motor (1112), and at the other end extends away from the power motor (1111) and covers the outer periphery of the cooling fan (1114). The first part of the external airflow can pass through the fan motor (1112), the cooling fan (1114) and the radiator (1113) in sequence. The second part of the external airflow can pass through the fan frame (1115), the fan blade (1403) of the cooling fan (1114) and the radiator (1113) in sequence along the axial direction of the power motor (1111). The third part of the external airflow first passes through the outer periphery of the fan frame (1115) radially, and then passes through the fan blade (1403) of the cooling fan (1114) and the radiator (1113) in sequence along the axial direction of the fan frame (1115).

15. The electric propulsion heat dissipation system according to claim 14, characterized in that, There is an installation gap between the fan motor (1112) and the power motor (1111) that connects to the inlet (1132). The fan motor (1112) is provided with a cooling channel (1201) for external airflow, so that the airflow in the installation gap can pass through the cooling channel (1201) through the fan motor (1112) and flow toward the inlet (1132).

16. The electric propulsion heat dissipation system according to claim 15, characterized in that, The orthographic projection of the radiator (1113) onto the corresponding surface of the arm (113) at least partially overlaps with the outlet (1135); Alternatively, the orthographic projection of the radiator (1113) onto the corresponding surface of the arm (113) is completely covered by the outlet (1135).

17. A power unit, characterized in that, The system includes a power battery and an electric propulsion cooling system (110) as described in any one of claims 1-16. The power battery is installed in the airframe structure of the aircraft and is electrically connected to the electric propulsion cooling system (110) to supply power to the electric propulsion cooling system (110).

18. An aircraft, characterized in that, It includes a fuselage (230), a wing (210), and an electric propulsion cooling system (110) as described in any one of claims 1-16, wherein the wing (210) is connected to the fuselage (230), and the electric propulsion cooling system (110) is installed on one or both of the wing (210) and the fuselage (230).

19. The aircraft according to claim 18, characterized in that, The aircraft is configured as an electric vertical takeoff and landing (EVTOL) aircraft.

Images