A flow-guiding device that enhances helicopter performance by utilizing the coupling of internal and external flow fields, and the helicopter itself.

Abstract

This invention discloses a flow diversion device and a helicopter that enhances helicopter performance by utilizing the coupling of internal and external flow fields. The flow diversion device includes a sliding support frame, a grooved stabilizing wing assembly, and a helical crossflow fan. The sliding support frame is disposed within the helicopter's fuselage and is slidably extendable to drive the grooved stabilizing wing assembly and the helical crossflow fan to extend through the mounting port and approach the air intake. The upper end of the grooved stabilizing wing assembly is recessed to form a mounting groove. The helical crossflow fan is rotatably mounted within the mounting groove and rotates under the action of the rotor downwash generated during helicopter rotor rotation. This rotation draws the rotor downwash and forward or side-flight turbulence into the mounting groove to form an accelerated airflow, which is then accelerated and discharged from the mounting groove before entering the air intake. This flow diversion device increases the intake volume and pressure of the engine, reduces most of the engine power loss caused by the coupling of internal and external flow fields, and improves engine output power.

Description

Technical Field

[0001] This invention relates to the field of engine technology, and in particular, to a flow diversion device that improves helicopter performance by utilizing the coupling of internal and external flow fields. Furthermore, this invention also relates to a helicopter including the aforementioned flow diversion device for improving helicopter performance by utilizing the coupling of internal and external flow fields. Background Technology

[0002] The rotor downwash of a conventional helicopter interferes with the helicopter fuselage, reducing the aerodynamic efficiency of the outflow and also affecting the engine intake. Conventional helicopters typically have 1-3 engines. For single-engine helicopters, the turboshaft engine intake is usually located at the top center of the fuselage, directly facing the incoming flow. The rotor downwash creates significant swirling in this area, resulting in installation losses. For helicopters with twin or three turboshaft engines, the engine intakes are generally located on the upper sides of the fuselage. The inlet airflow experiences swirling under the rotor downwash, and the differences between the intakes are significant, leading to installation losses. Furthermore, because turboshaft engines require multi-engine trim, inconsistent engine conditions result in additional losses. Generally, when the internal and external flow fields of a helicopter are coupled, the rotor downwash causes an installation loss of approximately 3-6% in engine power.

[0003] In existing helicopter design processes, due to the significant technical challenges of optimizing the coupling between internal and external flow involved in installation losses, minimizing these losses is generally not considered in helicopter design; a design approach emphasizing engine power surplus is typically adopted. Regarding turboshaft engine design, although some scholars and engineers have worked to reduce the loss coefficients of inlets or particle separators to improve engine output power, the improvements have been limited, and there are no methods or devices to actively enhance performance by utilizing the coupling of the helicopter's internal and external flow fields. In other aspects, such as forward flight (corresponding to the cruise state of turboshaft engines), methods have been employed to improve engine intake and reduce losses by designing guide channels in front of the inlet and integrating the fuselage shape into channels to guide airflow into the inlet. However, for helicopters, the power demand is greatest during hovering, where the power loss caused by the coupling between internal and external flow significantly impacts the helicopter's hovering takeoff capability.

[0004] The rotor flow field of conventional helicopters affects the entire aircraft, mostly through aerodynamic interference, reducing aerodynamic efficiency and also impacting engine intake. Higher intake pressure and velocity are more beneficial to the engine. Conventional engines are either mounted at the top center of the fuselage, with the intake directly facing the oncoming airflow, allowing forward speed to directly force air into the engine; or, to ensure that a failure in one engine does not affect the others, dual or multiple engines are arranged on the upper sides of the fuselage, with the intake ducts embedded inside the fuselage, relying on negative pressure to draw in air. Regardless of these two engine mounting methods, the addition of the rotor's rotating airflow causes coupling between the helicopter's internal and external flow fields, resulting in a power loss of approximately 3-6% due to the installation. Summary of the Invention

[0005] This invention provides a flow-guiding device and a helicopter that improves helicopter performance by utilizing the coupling of internal and external flow fields, thereby solving the technical problem of engine power loss caused by the coupling of internal and external flow fields due to the addition of rotating airflow from the rotor in existing helicopters.

[0006] The technical solution adopted in this invention is as follows:

[0007] A flow diversion device for improving helicopter performance by utilizing the coupling of internal and external flow fields is disclosed. The helicopter has an installation port on its fuselage near its air intake. The flow diversion device includes: a sliding support frame for mounting support, a grooved stabilizing wing assembly fixed to the sliding support frame, and a helical crossflow fan mounted on the grooved stabilizing wing assembly. The sliding support frame is located inside the helicopter's fuselage and is slidably extendable to drive the grooved stabilizing wing assembly and the helical crossflow fan to extend through the installation port closer to the air intake. The upper end of the grooved stabilizing wing assembly is recessed to form a mounting groove. The helical crossflow fan is rotatably mounted within the mounting groove to rotate under the action of the rotor downwash generated when the helicopter rotor rotates. This rotation draws the rotor downwash and forward or side-flight turbulence into the mounting groove to form an accelerated airflow, which is then accelerated out of the mounting groove and enters the air intake.

[0008] Furthermore, the helical crossflow fan includes a mounting shaft, multiple sets of supporting rotors fixed at intervals along the length of the mounting shaft, and multiple helical blades; the two ends of the mounting shaft are respectively rotatably supported on the groove stabilizing wing groups at both ends of the mounting groove; the multiple helical blades are arranged at intervals along the circumference, and each helical blade is fixed on the multiple sets of supporting rotors and extends in a helical shape along the axial direction of the mounting shaft.

[0009] Furthermore, the supporting rotor includes a mounting disk fixed on the outer circle of the mounting shaft, and multiple sets of support plates arranged sequentially at intervals along the circumference of the mounting disk; one end of each support plate is fixed to the outer circumferential surface of the mounting disk, and the opposite end extends freely toward the helical blade, or is fixed to the lower surface of the helical blade to support the helical blade.

[0010] Furthermore, the propeller blades are positive or negative helical blades with an installation angle of 20° to 90°; the number of propeller blades is 3 to 18; the helical direction of the propeller blades is set in accordance with the flow direction of the rotor downwash, so as to draw the rotor downwash and forward or side turbulence into the mounting groove; the rotation direction of the propeller blades is set in accordance with the flow direction of the accelerating airflow.

[0011] Furthermore, the grooved stabilizing airfoil assembly is also provided with a guide slope. The guide slope is located on the outflow side of the mounting groove, and its upper end is connected to the upper end of the outflow side of the mounting groove by a circular arc transition. The guide slope is used to guide the accelerated airflow to the corresponding air inlet. The spiral blade has an angle of 10° to 90° with the guide slope.

[0012] Furthermore, the mounting groove is an arc groove with an inwardly concave arc surface; the width of the spiral blade does not exceed 1 / 4 of the diameter of the arc surface of the arc groove; the maximum thickness of the spiral blade does not exceed 20% of its width; the height of the mounting groove on the air intake side is lower than the height of the guide slope, and the angle formed by the line connecting the top surface of the air intake side and the top surface of the guide slope with the horizontal plane is not greater than 15°, and the distance between the line connecting the top surface of the air intake side and the top surface of the guide slope and the center of the arc surface is less than 1 / 3 of the radius of the arc surface.

[0013] Furthermore, the helical crossflow fan also includes a one-way clutch for causing the mounting shaft to rotate in only one direction; the one-way clutch is fixed to the outer circumference of the mounting shaft.

[0014] Furthermore, the grooved stabilizing wing assembly includes a stabilizing wing body, two open end plates for supporting the mounting shaft, and bearing seats disposed on each open end plate; the top of the stabilizing wing body is recessed to form a mounting groove, which extends along the length of the stabilizing wing body and connects its two ends, so that the two ends of the stabilizing wing body respectively form a leading edge and a trailing edge, and one of the outer side walls of the stabilizing wing body forms a guide slope; the two open end plates are disposed at the two ends of the stabilizing wing body and are respectively fixed to the leading edge or trailing edge of the corresponding end; the two ends of the mounting shaft are rotatably supported on the bearing seats of the two open end plates respectively.

[0015] Furthermore, the open end plate is provided with ventilation holes that penetrate the plate surface; the grooved stabilizing airfoil assembly also includes flaps that are hinged to the two open end plates at both ends respectively. The flaps are located on the bottom side of the guide slope and extend along the extension direction of the helical blade.

[0016] According to another aspect of the present invention, a helicopter is also provided, including a fuselage and a flow diversion device as described above for improving the performance of the helicopter by coupling internal and external flow fields; the fuselage is provided with an air intake and an installation port; the flow diversion device is disposed in the fuselage compartment and slides close to the air intake of the air intake through the installation port.

[0017] The present invention has the following beneficial effects:

[0018] The airflow diversion device of this invention fully utilizes the characteristics of existing helicopter rotor downwash flow, pressurizing the airflow at the coupling point of internal and external flow fields and introducing it into the engine, thereby increasing the intake volume and pressure of the engine, reducing most of the engine power loss caused by the coupling of internal and external flow fields, and increasing the engine output power by more than 2%. The airflow diversion device of this invention has a wide range of applications, and can be used on conventional helicopters as well as on the air intakes of other aircraft using turboshaft and turboprop engines. It can be applied to single-engine, twin-engine, or multi-engine helicopters, and has broad application prospects. During operation, the rotor downwash flow is circumferentially rotating and flows downward at high speed. The flow field is basically symmetrical when hovering, but the flow field on the left and right sides of the fuselage is asymmetrical during forward flight. The device of this invention uses different crossflow fan spiral twisting directions on the engine air intakes on both sides of the helicopter fuselage, thereby adapting to the differences caused by the different flow directions of the rotor downwash flow on different sides of the engine. The device of this invention has low additional cost, is lightweight, does not require additional power, and has relatively small wind resistance caused by the airflow obstruction caused by the rotor downwash flow and forward flight, accounting for less than 0.5% of the total wind resistance of the aircraft, which can be ignored.

[0019] The helicopter of this invention not only increases the intake air volume and intake pressure of the engine, reducing most of the engine power loss caused by the coupling of internal and external processes, but also improves the engine output power by more than 2%. Furthermore, it has a wide range of applications, suitable for both conventional helicopters and other aircraft using turboshaft or turboprop engines. It can be applied to single-engine, twin-engine, or multi-engine helicopters, showing broad application prospects. It can also adapt to the differences caused by the different flow directions of the rotor downwash on different sides of the engine. The device of this invention has low additional cost, is lightweight, requires no additional power, and has relatively low drag caused by airflow obstruction due to rotor downwash and forward flight, accounting for less than 0.5% of the total aircraft drag, which can be ignored.

[0020] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0021] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0022] Figure 1 This is a schematic diagram of the spatial structure of a flow-guiding device for improving helicopter performance by utilizing the coupling of internal and external flow fields, according to a preferred embodiment of the present invention.

[0023] Figure 2 yes Figure 1Schematic diagram of the spatial structure of a spiral crossflow fan;

[0024] Figure 3 yes Figure 1 Schematic diagram of the spatial structure of the central groove stabilizing airfoil assembly;

[0025] Figure 4 yes Figure 1 Schematic diagram of the cross-section of the central drainage device;

[0026] Figure 5 This is a schematic diagram of the working principle of a spiral crossflow fan;

[0027] Figure 6 This is a flow field pressure contour map of a helical crossflow fan;

[0028] Figure 7 This is a schematic diagram showing the main parameters affecting the working performance of the drainage device;

[0029] Figure 8 This is a schematic diagram of the spatial structure of a helicopter according to a preferred embodiment of the present invention.

[0030] Legend

[0031] 10. Helicopter; 101. Air intake; 11. Fuselage; 21. Mounting connector; 30. Groove stabilizing wing assembly; 301. Mounting groove; 3010. Arc surface; 302. Guide slope; 31. Stabilizing wing body; 32. Open end plate; 321. Vent; 33. Bearing housing; 34. Flap; 40. Helical crossflow fan; 41. Mounting shaft; 42. Support rotor; 421. Mounting plate; 422. Support plate; 43. Helical blade; 44. One-way clutch. Detailed Implementation

[0032] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0033] Reference Figure 1 and Figure 8A preferred embodiment of the present invention provides a flow diversion device for improving helicopter performance by utilizing the coupling of internal and external flow fields. An installation port is provided on the fuselage 11 of the helicopter 10 near its air intake 101. The flow diversion device includes: a sliding support frame for installation support, a grooved stabilizing wing assembly 30 fixed to the sliding support frame, and a spiral crossflow fan 40 mounted on the grooved stabilizing wing assembly 30. The sliding support frame is disposed inside the fuselage of the helicopter 10 and is slidably telescopic to drive the grooved stabilizing wing assembly 30 and the spiral crossflow fan 40 to extend through the installation port closer to the air intake 101. The upper end of the grooved stabilizing wing assembly 30 is recessed to form an installation groove 301. The spiral crossflow fan 40 is rotatably mounted within the installation groove 301 to rotate under the action of the rotor downwash generated when the helicopter 10 rotor rotates. This allows the rotor downwash and forward or side-flight turbulence to be drawn into the installation groove 301 to form an accelerated airflow, which is then accelerated out of the installation groove 301 and enters the air intake 101.

[0034] During operation, the sliding support frame is activated, and the sliding motion drives the grooved stabilizing wing assembly 30 and the spiral crossflow fan 40 through the mounting port opened on the fuselage 11 to the air intake 101 of the corresponding air intake duct on the helicopter 10. In actual design, the number of air intake ducts on the fuselage 11 corresponds to the number of sets of air intake devices. Then, the spiral crossflow fan 40 rotates under the action of the rotor downwash and the forward or side turbulence, drawing the rotor downwash and the forward or side turbulence into the mounting groove 301 to form an accelerated airflow. This accelerated airflow is then accelerated and discharged from the exhaust side of the mounting groove 301 by the spiral crossflow fan 40 and enters the corresponding air intake 101.

[0035] The airflow diversion device of this invention fully utilizes the characteristics of existing helicopter rotor downwash flow, pressurizing the airflow at the coupling point of internal and external flow fields and introducing it into the engine. This increases the intake volume and pressure of the engine, reduces most of the engine power loss caused by the coupling of internal and external flow fields, and improves the engine output power by more than 2%. The airflow diversion device of this invention has a wide range of applications, and can be used on conventional helicopters as well as on the air intakes of other aircraft using turboshaft and turboprop engines. It can be applied to single-engine, twin-engine, or multi-engine helicopters, and has broad application prospects. During operation, the rotor downwash flow is circumferentially rotating and flows downward at high speed. The flow field is basically symmetrical when hovering, but the flow field on the left and right sides of the fuselage is asymmetrical during forward flight. The device of this invention uses different crossflow fan spiral twisting directions on the engine air intakes on both sides of the helicopter fuselage, which can adapt to the differences caused by the different flow directions of the rotor downwash flow on different sides of the engine. The device of this invention has low additional cost, is lightweight, does not require additional power, and has relatively small drag caused by the airflow obstruction caused by the rotor downwash flow and forward flight, accounting for less than 0.5% of the total aircraft drag, which can be ignored.

[0036] Optionally, such as Figure 2 As shown, the helical crossflow fan 40 includes a mounting shaft 41, multiple sets of supporting rotors 42 that are fixedly fixed to the mounting shaft 41 at intervals along its length, and multiple helical blades 43. The two ends of the mounting shaft 41 are rotatably supported on the groove stabilizing wing assemblies 30 at both ends of the mounting groove 301. The multiple helical blades 43 are arranged at intervals along the circumference, and each helical blade 43 is fixed to the multiple sets of supporting rotors 42, extending in a helical shape along the axial direction of the mounting shaft 41.

[0037] In this optional solution, such as Figure 2 As shown, the supporting rotor 42 includes a mounting disk 421 fixed to the outer circumference of the mounting shaft 41, and multiple sets of support plates 422 arranged sequentially at intervals along the circumference of the mounting disk 421. One end of each support plate 422 is fixed to the outer circumferential surface of the mounting disk 421, and the opposite end extends freely toward the helical blade 43, or is fixed to the lower surface of the helical blade 43 to support the helical blade 43. In a specific embodiment of this optional solution, as shown... Figure 2 As shown, the supporting rotor includes two sets of identical turbine rotors and a support frame, with one set of turbine rotors positioned close to the end of the grooved stabilizing airfoil assembly 30. The support plates 422 of the turbine rotors are short blades with airfoils, part of which are fixed to the lower surface of the helical blades 43; the support plates 422 of the support frame are arranged corresponding to the number of helical blades 43, with each support plate 422 fixedly supporting one helical blade 43.

[0038] In this optional solution, such as Figure 2 As shown, the cross-section of the helical blade 43 can be rectangular, willow-leaf shaped, crescent-shaped, or airfoil, etc. The helical blade 43 is a positive or negative helical blade with an installation angle of 20° to 90°. The installation angle is set to prevent pulsating vibration caused by the blade rotating and driving the airflow into the grooved stabilizing airfoil assembly 30. That is, a straight or small-angle helical blade will compress the airflow when it passes the guide slope 302 and release the pressure after leaving, causing vibration. This angle range avoids the occurrence of vibration. The number of helical blades 43 is 3 to 18. The aerodynamic performance is optimal when the number of helical blades 43 is within this range. Exceeding this range will result in insufficient or excessive blade area, leading to a decrease in aerodynamic and flow field performance. The helical direction of the helical blade 43 is set in accordance with the flow direction of the rotor downwash to draw the rotor downwash and forward or side-fly turbulence into the installation groove 301. Similarly, the direction of rotation of the helical blade 43 is set to follow the flow direction of the accelerating airflow so that it rotates under the action of the accelerating airflow.

[0039] In this optional solution, such as Figure 2 and Figure 3As shown, the grooved stabilizing airfoil assembly 30 is also provided with a guide slope 302. The guide slope 302 is located on the outflow side of the mounting groove 301, and its upper end is connected to the upper end of the outflow side of the mounting groove 301 by a rounded transition. The guide slope 302 is used to guide the accelerated airflow to the corresponding air inlet 101. During operation, the guide slope 302 is the rear end of the upper airfoil of the mounting groove 301 stabilizing airfoil, and is mainly used to draw out the airflow driven by the helical blade 43 and accelerate it away from the mounting groove 301. The helical blade 43 and the guide slope 302 have an angle of 10° to 90°. Since the helical blade 43 has a positive or negative helix with an installation angle of 20° to 90°, this angle is created to reduce the pulsating impact vibration of the airflow.

[0040] In this optional solution, such as Figure 4-7 As shown, the mounting groove 301 is an arc-shaped groove with an inwardly concave arc surface 3010. The width of the helical blade 43 does not exceed 1 / 4 of the diameter of the arc surface 3010 of the arc groove; this arrangement is to ensure sufficient space within the arc groove to generate an eccentric low-pressure vortex belt, diverting the external high-pressure airflow, and ultimately directing more airflow towards the intake. The maximum thickness of the helical blade 43 does not exceed 20% of its width; this arrangement is to allow sufficient airflow to pass through the high-speed rotating helical blade 43 and flow towards the guide ramp 302, thereby allowing more airflow to enter the intake. The height of the air intake side of the mounting groove 301 is lower than the height of the guide slope 302, and the angle formed by the line connecting the top surface of the air intake side and the top surface of the guide slope 302 with the horizontal plane is no greater than 15°. The distance between the line connecting the top surface of the air intake side and the top surface of the guide slope 302 and the center of the arc surface 3010 is less than 1 / 3 of the radius of the arc surface 3010. This setting is to attract more incoming air from the front and above. Under the action of the rotation of the spiral blades 43, part of the airflow is accelerated through the guide slope 302, and part of the airflow is rotated to generate an eccentric vortex, thereby improving the aerodynamic efficiency of the entire device.

[0041] Preferably, such as Figure 2 As shown, the helical crossflow fan 40 also includes a one-way clutch 44 for rotating the mounting shaft 41 in only one direction. The one-way clutch 44 is fixed to the outer circumference of the mounting shaft 41. In design, the direction of rotation of the one-way clutch 44 must be such that the air intake device draws airflow from the outside.

[0042] Optionally, the diversion device of the present invention further includes an external helicopter drive source connected to the mounting shaft 41 to drive it to rotate, thereby driving the spiral crossflow fan 40 to rotate.

[0043] The working principle of the drainage device of this invention is as follows: Figure 5 and Figure 6As shown, with the spiral crossflow fan 40 rotating, the entire device absorbs airflow from all directions. The airflow is gathered into the spiral crossflow fan 40 and then flows smoothly under the action of the blades (support plate 422 and spiral blade 43). The airflow detaches when the blades pass the guide slope 302. Due to the action of the mounting groove 301 and the rotating blades, a low-pressure vortex is formed inside the entire flow-guiding device, deviating from the center and pointing downwards. A low static pressure zone is also formed where the accelerated airflow passes the guide slope 302. The accelerated airflow is discharged from the guide slope 302... Simultaneously, it gains reverse thrust, resulting in a large lift-to-drag ratio for the diversion device. With less energy consumption, the diversion device can convert the direction of the airflow and achieve accelerated rotation of the helical crossflow fan 40 by absorbing external airflow energy. Furthermore, the helical blades 43 are helical, which can better utilize the lateral and circumferential velocities of the rotor downwash to absorb the downwash energy and convert it into airflow energy entering the intake duct. The addition of the turbine rotor further absorbs the lateral airflow into the mounting groove 301, and then transmits it to the guide slope 302 for output through the action of the helical blades 43.

[0044] Optionally, such as Figure 3 As shown, the grooved stabilizing wing assembly 30 includes a stabilizing wing body 31, two open end plates 32 for supporting the mounting shaft 41, and bearing seats 33 disposed on each open end plate 32. The top of the stabilizing wing body 31 is recessed to form a mounting groove 301, which extends along the length of the stabilizing wing body 31 and connects its two ends, so that the two ends of the stabilizing wing body 31 respectively form a leading edge 311 and a trailing edge, and one of the outer side walls of the stabilizing wing body 31 forms a guide slope 302. The two open end plates 32 are respectively disposed at both ends of the stabilizing wing body 31 and fixed to the leading or trailing edge of the corresponding end. The two ends of the mounting shaft 41 are rotatably supported on the bearing seats 33 of the two open end plates 32.

[0045] In this optional solution, such as Figure 3 As shown, the open end plate 32 is provided with a vent 321 that penetrates the plate surface. The vent 321 is used for ventilation, absorbing external airflow into the air intake device and guiding it to the engine's air intake. The grooved stabilizing airfoil assembly 30 also includes flaps 34 that are hinged to the two open end plates 32 at both ends. The flaps 34 are located on the bottom side of the guide ramp 302 and extend along the extension direction of the propeller blade 43. During operation, the flaps 34 act as trailing edge adjustment flaps of the grooved stabilizing airfoil assembly 30, functioning like flaps. They can be deflected around the guide ramp 302 by manipulation to guide the airflow direction.

[0046] The airflow guiding device of this invention is simple to operate. By automatically adjusting the flap angle 34 and the rotation speed of the helical crossflow fan 40, it can keep guiding sufficient airflow into the air intake, which is caused by changes in the rotor downwash wind speed and direction due to changes in the rotor disk load, as well as changes in the rotor downwash wind direction caused by different helicopter flight speeds or by changes in rotor downwash wind direction when the helicopter is hovering or flying forward at low to medium speeds. Under the mixed effect of the rotor downwash and forward airflow or crosswind turbulence, when air enters the device in the X, Y, and Z directions, it will drive the helical crossflow fan 40 to rotate normally, and the helical crossflow fan 40 will guide the airflow into the air intake.

[0047] Optionally, such as Figure 3 As shown, the sliding support frame includes a mounting joint 21 fixed to the end of the grooved stabilizing wing assembly 30, and a telescopic cylinder connecting the mounting joint 21. The telescopic cylinder is located inside the fuselage compartment of the fuselage 11, extends out of the fuselage when in operation, and retracts into the fuselage compartment when not in operation.

[0048] Reference Figure 8 A preferred embodiment of the present invention also provides a helicopter, including a fuselage 11 and an air intake device as described above for improving helicopter performance by coupling internal and external flow fields. The fuselage 11 is provided with an air intake and a mounting port. The air intake device is disposed within the fuselage compartment of the fuselage 11 and slides close to the air intake 101 of the air intake via the mounting port. The helicopter of the present invention includes a flow-guiding device that improves helicopter performance by utilizing the coupling of internal and external flow fields, as described in any of the above claims. Therefore, it can increase the intake volume and intake pressure of the engine, reduce most of the installation loss of engine power caused by the coupling of internal and external flow fields, and increase the engine output power by more than 2%. It has a wide range of applications, and can be used on conventional helicopters as well as on the air intakes of other aircraft using turboshaft and turboprop engines. It can be applied to single-engine, twin-engine, or multi-engine helicopters, and has broad application prospects. It can also adapt to the differences caused by the different flow directions of the rotor downwash on different sides of the engine. The device of the present invention has low additional cost, is lightweight, does not require additional power, and has relatively low wind resistance caused by the airflow obstruction caused by the rotor downwash and forward flight, accounting for less than 0.5% of the total wind resistance of the aircraft, which can be ignored.

[0049] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A flow guiding device for improving the performance of a helicopter by coupling the inner and outer flow fields, characterized in that, The body (11) of the helicopter (10) is provided with a mounting opening near the air inlet (101), and the flow guiding device comprises: a sliding support frame serving as a mounting support, a concave stabilizer group (30) fixed to the sliding support frame, and a spiral cross-flow fan (40) mounted on the concave stabilizer group (30); the sliding support frame is arranged in the cabin of the body of the helicopter (10) and is slidingly and telescopically arranged to drive the concave stabilizer group (30) and the spiral cross-flow fan (40) to extend through the mounting opening and approach the air inlet (101); the upper end of the concave stabilizer group (30) is concave to form a mounting concave groove (301), and the spiral cross-flow fan (40) is rotatably mounted in the mounting concave groove (301) to rotate under the rotor downwash flow generated when the rotor of the helicopter (10) rotates, to suck the rotor downwash flow and the forward flight airflow or the side flight disturbance airflow into the mounting concave groove (301) to form accelerated airflow, and to make the accelerated airflow accelerate and exit the mounting concave groove (301) to enter the air inlet (101); the spiral cross-flow fan (40) comprises a mounting shaft (41), a plurality of groups of support rotors (42) fixed to the mounting shaft (41) along the length direction of the mounting shaft (41), and a plurality of spiral blades (43); the cross section of the spiral blade (43) is one of a rectangular shape, a willow leaf shape, a crescent shape, or an airfoil shape; the spiral blade (43) is a positive spiral or a reverse spiral blade with an installation angle of 20°-90°, to avoid the generation of vibration phenomenon; the number of the spiral blades (43) is 3-18; the spiral direction of the spiral blade (43) is arranged in accordance with the flow direction of the rotor downwash flow, to suck the rotor downwash flow and the forward flight airflow or the side flight disturbance airflow into the mounting concave groove (301); and the turning direction of the spiral blade (43) is arranged in accordance with the flow direction of the accelerated airflow, to rotate under the action of the accelerated airflow.

2. The flow guiding device for improving the performance of a helicopter by coupling internal and external flow fields according to claim 1, wherein the two ends of the mounting shaft (41) are rotatably supported on the concave stabilizer group (30) at the two ends of the mounting concave groove (301); the plurality of spiral blades (43) are circumferentially and sequentially arranged, and each spiral blade (43) is fixed to the plurality of groups of support rotors (42) and extends in a spiral shape along the axial direction of the mounting shaft (41).

3. The flow guiding device for improving the performance of a helicopter by coupling internal and external flow fields according to claim 2, wherein the support rotor (42) comprises a mounting disc (421) fixed to the outer circle of the mounting shaft (41), and a plurality of groups of support pieces (422) sequentially and spacedly arranged along the circumferential direction of the mounting disc (421); one end of each support piece (422) is fixed to the outer circumferential surface of the mounting disc (421), and the opposite end thereof freely extends toward the spiral blade (43), or is fixed to the lower surface of the spiral blade (43) to support the spiral blade (43).

4. The flow guiding device for improving the performance of a helicopter by coupling internal and external flow fields according to claim 2, wherein The guiding slope (302) is located at the outflow side of the installation groove (301), and the upper end of the guiding slope (302) is connected with the upper end of the outflow side of the installation groove (301) through a circular arc transition, and the guiding slope (302) is used for guiding the accelerated airflow to the corresponding air inlet (101); The helical blade (43) and the guiding slope (302) have an included angle of 10-90 degrees.

5. The flow guiding device for improving the performance of a helicopter by coupling internal and external flow fields according to claim 4, characterized in that, The installation groove (301) is a circular arc groove with an inner concave circular arc surface (3010); The width of the helical blade (43) is not more than 1 / 4 of the diameter of the circular arc surface (3010) of the circular arc groove; The maximum thickness of the helical blade (43) is not more than 20% of the width of the helical blade (43); The height of the air inlet side of the installation groove (301) is lower than the height of the guiding slope (302), and the angle formed by the connecting line between the top surface of the air inlet side and the top surface of the guiding slope (302) and the horizontal plane is not more than 15 degrees, and the distance between the connecting line between the top surface of the air inlet side and the top surface of the guiding slope (302) and the center of the circular arc surface (3010) is less than 1 / 3 of the radius of the circular arc surface (3010).

6. The flow guiding device for improving the performance of a helicopter by coupling internal and external flow fields according to claim 2, characterized in that, The helical cross-flow fan (40) further comprises a one-way clutch (44) for rotating the installation rotating shaft (41) in only one direction; The one-way clutch (44) is fixed on the outer circle of the installation rotating shaft (41).

7. The flow guiding device for improving the performance of a helicopter by coupling internal and external flow fields according to claim 4, characterized in that, The recessed stabilizer wing set (30) comprises a stabilizer wing body (31), two open end plates (32) for supporting the installation rotating shaft (41), and bearing seats (33) arranged on each open end plate (32); The top of the stabilizer wing body (31) is concave to form an installation groove (301), and the installation groove (301) extends along the length direction of the stabilizer wing body (31) to communicate with both ends of the stabilizer wing body (31), so that the two ends of the stabilizer wing body (31) form a leading edge (311) and a trailing edge, respectively, and one of the outer side walls of the stabilizer wing body (31) forms a guiding slope (302); The two open end plates (32) are arranged at the two ends of the stabilizer wing body (31), respectively, and are fixed with the leading edge or the trailing edge of the corresponding end; The two ends of the installation rotating shaft (41) are rotatably supported on the bearing seats (33) of the two open end plates (32), respectively.

8. The flow guiding device for improving the performance of a helicopter by coupling internal and external flow fields according to claim 7, characterized in that, The open end plate (32) is provided with an air hole (321) penetrating through the plate surface; The recessed stabilizer wing set (30) further comprises two flap pieces (34) hingedly connected with the two open end plates (32) at the two ends, respectively, and the flap pieces (34) are located at the bottom side of the guiding slope (302) and extend along the extension direction of the helical blade (43).

9. A helicopter characterized by The helicopter comprises a fuselage (11) and the flow guiding device for improving the performance of a helicopter by coupling internal and external flow fields according to any one of claims 1-8. The air inlet channel and the mounting port are arranged on the fuselage (11); The air inlet channel and the mounting port are arranged on the fuselage (11);

Images