Concealed underwater propeller with conformal vector nozzle

Abstract

The invention discloses a built-in underwater propeller with conformal vector nozzles. The built-in underwater propeller comprises a flow channel installed in an aircraft and propeller units arranged in the flow channel. An inlet section of the flow channel is communicated with an external water body of the aircraft; the propeller unit comprises a propelling motor, an impeller, a guide vane, a vector nozzle and the like; the vector nozzle is a horn-shaped rotary body, when the vector nozzle is located at a first working position where the vector nozzle rotates by 0 degree and a second working position where the vector nozzle rotates by 180 degrees, the outer surface of the vector nozzle is attached to the outer envelope surface of the aircraft in a conformal mode, and the included angle between the nozzle outflow direction of the vector nozzle and the axis of the aircraft ranges from 10 degrees to 20 degrees. According to the invention, on the premise of ensuring the appearance fairing and stealth performance of the rotary underwater vehicle, the integration of complete built-in of the propulsion device, efficient propulsion and multi-direction vector control is realized.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of underwater propellers, and particularly relates to a built-in underwater propeller with a conformal vector nozzle. BACKGROUND

[0002] With the rapid growth of the demand for tasks such as ocean exploration, underwater engineering operation, ocean environment monitoring, and military reconnaissance and attack, the performance requirements of underwater vehicles (including AUV, UUV, ROV, etc.) are continuously improved. High-performance underwater vehicles not only need to have high propulsion efficiency and long endurance, but also need to realize multi-degree-of-freedom high-maneuvering control capabilities such as hovering, zero-radius turning, heaving, and transverse moving under the constraints of limited space and complex environment, and also need to take into account low noise, low resistance, and high reliability.

[0003] The existing mainstream underwater propulsion and control schemes mainly include: 1. Propeller / ducted propeller + rudder plate scheme. Conventional submarines and surface ships generally use propellers or ducted propellers to provide main thrust, and control the direction through rudder plates arranged behind the propeller or at the tail of the ship body. This scheme is mature in technology and simple in structure, but has the following problems: near low speed or zero speed, the rudder plate has a large decrease in water flow deflection ability, the steering efficiency is low, and it is difficult to realize precise hovering, fixed-point tracking and other actions; the propeller and the rudder plate are mostly arranged externally, which is not conducive to drag reduction and noise control.

[0004] 2. Slot propeller auxiliary control scheme. Some ships / boats are provided with transverse or vertical through slots at the bow, stern or side, and transverse propellers are arranged in the slots for parking, low-speed transverse moving or attitude fine adjustment control. This scheme can enhance the low-speed maneuvering ability to a certain extent, but the slot destroys the continuity and streamline of the ship body shell, resulting in strong vortex and additional resistance in the slot at high speed, which significantly reduces the speed and propulsion efficiency; the thrust of the small propeller in the slot is limited, and it is difficult to meet the requirements of propulsion and control integration of high-maneuvering underwater vehicles.

[0005] 3. Multiple externally mounted propeller units. Multiple independently rotatable ducted propeller units are installed at different positions (such as bow, stern, and side) outside the vehicle. By controlling the thrust size and direction of each propeller unit, complex maneuvers can be achieved. This multi-propeller layout is flexible in control, but has reliability and resistance problems: the external propeller and its support structure protrude from the boat body, which is easy to collide, entangle or damage in complex underwater environment; the exposed structure significantly increases the wet surface area and shape resistance of the vehicle, reduces the endurance performance, and increases the propeller noise.

[0006] 4. Built-in thruster. In the prior art, the propulsion device is built into the hull shell, water is introduced through the internal flow channel, the impeller works, and the fairing realizes thrust output, so as to reduce entanglement and noise. Some schemes realize limited forward / backward switching by turning the fairing or baffle, but still have the following problems: the propulsion direction has limited freedom, and it is difficult to realize multi-directional vector thrust in a true sense; the nozzle is usually arranged along the axial direction of the hull, and it is difficult to be directly used for lateral or vertical thrust output.

[0007] 5. External vector water jet / vector nozzle technology. On the surface unmanned ship, amphibious vehicle and other platforms, there are various vector water jet or vector nozzle schemes, which realize jet flow direction control through deflectable nozzle or multiple nozzle switching. These schemes usually arrange the nozzle or nozzle at the external position of the tail of the boat / car, and rely on hydraulic cylinders, rudders or servo motors to realize pitch and azimuth deflection. The common defects include: the protruding nozzle seriously damages the streamline of the hull, and the higher the speed, the greater the additional resistance; high-speed jet flow impacts the exposed vector mechanism, and the structural fatigue and reliability problem is prominent; mainly for water surface ship / car platform, without considering the conformal arrangement and stealth requirements of the underwater vehicle of the rotating body.

[0008] In summary, the existing technology in the propulsion and control of the underwater vehicle of the rotating body mainly has the following technical problems: (1) Propulsion and multi-directional maneuvering are difficult to be integrated: the traditional propeller+rudder plate or built-in+baffle scheme can only adjust the thrust in limited directions, and it is difficult to realize true three-dimensional multi-directional vector propulsion on the rotating body vehicle.

[0009] (2) The shape is damaged, resulting in increased resistance: the external propeller, protruding nozzle or embedded nozzle through the recess cavity all damage the smoothness of the hull shell to different degrees, and form obvious additional resistance and vortex when sailing at high speed.

[0010] (3) Insufficient structural reliability and environmental adaptability: exposed propulsion components are prone to collision and entanglement, and external vector mechanisms are prone to fatigue failure due to water flow impact, which is difficult to meet the long-term underwater high-reliability operation requirements.

[0011] (4) Acoustic stealth and propulsion structure are not designed in coordination: most schemes only focus on propulsion and control, and the comprehensive design of flow channel, shell and sound-absorbing material is insufficient, and the noise control level is limited.

[0012] (5) Lack of overall structural solution for "rotating body vehicle+conformal vector nozzle+complete built-in": there are few schemes in the public literature that systematically design the conformal relationship between the vector nozzle and the shell.

[0013] Therefore, it is necessary to provide a novel propelling structure for a water underwater vehicle of a rotary body, to realize that the propelling device is completely hidden in the outer envelope surface of the body, the nozzle is a rotatable conformal segment of the shell, and the low resistance of the body shape is maintained as much as possible in different vector working positions, the internal high-efficiency axial flow pump and optimized flow channel are adopted to realize high efficiency and low noise, and the multiple propelling units are coordinated to realize high maneuvering control of six degrees of freedom. SUMMARY

[0014] The application provides a hidden underwater propeller with a conformal vector nozzle, which realizes the integration of complete hiding of the propelling device, high-efficiency propelling and multi-directional vector control under the premise of ensuring the smoothness and stealth performance of the outer shape of the underwater vehicle of the rotary body.

[0015] The application provides a hidden underwater propeller with a conformal vector nozzle, which realizes the integration of complete hiding of the propelling device, high-efficiency propelling and multi-directional vector control under the premise of ensuring the smoothness and stealth performance of the outer shape of the underwater vehicle of the rotary body. The flow channel comprises an inlet section, an impeller section, a guide vane section and an outlet bending section; the inlet section is in communication with the water outside the vehicle and is provided with an inlet grid. The propeller unit comprises a propelling motor and an impeller arranged in the impeller section, a guide vane arranged in the guide vane section, a vector nozzle arranged in the outlet bending section and a nozzle servo motor for driving the rotation of the vector nozzle. The vector nozzle is a horn-shaped rotary body and constitutes a rotatable segment of the shell of the vehicle; when the vector nozzle is in a first working position of 0° rotation and a second working position of 180° rotation, the outer surface of the vector nozzle is conformal to the outer envelope surface of the vehicle, and the included angle between the nozzle outflow direction of the vector nozzle and the axis of the vehicle is 10°-20°; when the vector nozzle is in other working positions, the maximum radial deviation of the outer surface of the vector nozzle relative to the outer envelope surface of the vehicle is not more than 10% of the radius of the shell of the vehicle at the position.

[0016] Further, the vector nozzle is connected with the fixed support structure arranged on the shell of the vehicle or the flow channel through a nozzle rotating bearing. The output shaft of the nozzle servo motor is connected with a driving gear, the driving gear is engaged with the gear ring of the outer circumference of the vector nozzle, and the controlled rotation of the vector nozzle around its own axis is realized under the driving of the nozzle servo motor.

[0017] Preferably, the maximum radial deviation of the outer surface of the vector nozzle relative to the outer envelope surface of the vehicle is not more than 5% of the radius of the shell of the vehicle at the position.

[0018] Further, when the vector nozzle is in the first working position, the nozzle outflow direction of the vector nozzle points to the stern direction of the vehicle; when the vector nozzle is in the second working position, the nozzle outflow direction of the vector nozzle points to the bow direction of the vehicle.

[0019] Preferably, the flow channel adopts a composite material or a corrosion-resistant metal material, and a porous sound-absorbing material layer is attached to the inner wall of the flow channel for absorbing noise generated by the impeller and turbulence.

[0020] Further, the propelling motor is connected with the impeller through a main shaft, and the main shaft is supported and positioned in front and back directions by support bearings and water-lubricated bearings.

[0021] Further, the propelling motor is connected with the main shaft through a dynamic seal, and the dynamic seal adopts a multi-stage sealing structure, including an elastic sealing ring, a rigid blocking ring and a sealing cavity filled with lubricating grease, for preventing water from entering the interior of the propelling motor.

[0022] Further, the guide vane includes a plurality of guide vanes uniformly arranged on a ring-shaped guide vane ring, and the inlet edge angle of the guide vane is matched with the flow velocity direction of water flow at the outlet of the impeller, for eliminating the rotating component of the water flow discharged by the impeller and making the water flow enter the outlet bending section in a nearly axial direction.

[0023] Further, the inlet section of the flow channel is a converging section for converging and accelerating the water flow passing through the inlet grating, the impeller section and the guide vane section are straight pipe sections with equal cross sections, and the outlet bending section is a curved pipe section with continuous curvature variation, and the curvature monotonically or slowly varies along the flow direction, so that the water flow keeps attached flow during the bending process and the local energy loss is reduced.

[0024] Further, the underwater vehicle is internally provided with four flow channels, two of which are arranged opposite to each other at the front of the underwater vehicle, and the other two are arranged opposite to each other at the rear of the underwater vehicle. The propelling motor and the jet nozzle servo motor in each flow channel are connected with a control system, and the control system controls the thrust size of each propelling motor and the pointing angle of the vector jet nozzle, so that the underwater vehicle realizes the attitude and trajectory control of forward movement, backward movement, upward floating, downward diving, lateral movement, as well as pitching, yawing and rolling.

[0025] Compared with the prior art, the present application has the following beneficial effects: 1. The shape of the boat body is completely smooth under the main working condition, and the shape disturbance is controlled within a limited range under other vector working conditions, and the additional resistance is significantly reduced: The vector nozzle is designed as a rotatable segment of the shell: when the nozzle is in the forward working condition (the nozzle points to the first working position of the stern) and the reverse / braking working condition (the nozzle points to the second working position of the bow), the outer surface of the nozzle conforms to the nominal envelope surface of the shell of the revolving body, is geometrically continuous at least in the normal direction at the connection, and makes the overall shape of the vehicle in the forward working condition geometrically smooth without forming steps or pits; when the nozzle is deflected to the vector working condition for heaving, transverse movement and the like, the outer surface of the nozzle will locally deviate from the nominal envelope surface, but through geometric constraints on the nozzle shape and the deflection angle range, the local protrusions or depressions can be controlled within the design allowable range; the shape in the reverse / braking working condition is also basically smooth and continuous; thereby the maneuverability is ensured while the influence of shape disturbance on the sailing resistance is minimized.

[0026] 2. High integration of propulsion and multidirectional vector control: The present application realizes 360° continuous vector thrust adjustment capacity of the propulsion device through the overall design of "axial impeller + guide vane + bent flow passage + conformal vector nozzle", while the propulsion device is internally housed and streamlined. A single propulsion module can generate thrust in different directions, and multiple modules can realize complex maneuvers in six degrees of freedom, thereby significantly improving the hovering capability, attitude control capability and local fine operation capability of the vehicle.

[0027] 3. Safe and reliable structure internally housed, strong environmental adaptability: The impeller, shafting, nozzle and driving mechanism of the propeller are all arranged inside the hull shell, only the nozzle opening is connected with the external water body, there are no exposed blades, nozzles or rudder plates, and the risk of collision, entanglement and mechanical damage is greatly reduced; the nozzle is supported by high-stiffness cross-roller bearings and enveloped by the shell, thereby greatly improving the impact resistance and fatigue resistance of the structure and adapting to complex underwater terrain and long-term operation requirements.

[0028] 4. Low noise and high concealment: The internally housed impeller cooperates with the guide vane, the composite material flow passage and the sound-absorbing lining to form an envelope structure having noise absorption and shielding effect, thereby controlling the radiation of impeller and turbulent noise; the conformal shape avoids local mutation and vortex separation, thereby reducing flow-induced noise and structural vibration noise. The propeller of the present application is suitable for high-concealment underwater tasks and platforms with acoustic sensors.

[0029] 5. High working condition adaptability and system integration: Through the collaborative optimization of the flow channel geometry and the blade guide vane profile, the propeller of the application can maintain high-efficiency and stable flow and thrust output under non-design conditions such as straight sailing, oblique sailing, yawing, lateral micro-motion, etc., avoiding the problem of sharp decline in efficiency of the traditional propeller+rudder plate scheme at large deflection angles. At the same time, the propeller module is uniform in form, facilitating modular arrangement at different positions and integration with the overall structure of the vehicle.

[0030] Through the synergy of the above structure and technical effects, the application is not simply a superposition of "built-in propulsion + vector nozzle + noise reduction measures", but a new system-level technical solution that bundles conformal geometry, bearing structure, internal flow channel and acoustic optimization together around the scenario of underwater vehicles with rotating bodies, which has significant substantial features and significant progress over the prior art. BRIEF DESCRIPTION OF DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the application, the drawings needed in the embodiment description will be briefly introduced as follows. 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.

[0032] Figure 1 The figure is a schematic diagram of the arrangement and overall structure of the propeller unit of the application on the underwater vehicle with rotating body.

[0033] Figure 2 The figure is a schematic diagram of the cooperation of the nozzle servo motor and the vector nozzle of the application.

[0034] Figure 3 The figure is a schematic diagram of the structure of the vector nozzle of the application.

[0035] Figure 4 The figure is a schematic diagram of the principle of the propeller unit of the application.

[0036] Figure 5 The figure is a working schematic diagram of the propeller unit of the application when used for forward motion of the vehicle.

[0037] Figure 6 The figure is a working schematic diagram of the propeller unit of the application when used for backward motion of the vehicle.

[0038] Figure 7 The figure is a working schematic diagram of the propeller unit of the application when used for heaving motion of the vehicle.

[0039] Figure 8 The figure is a working schematic diagram of the propeller unit of the application when used for transverse motion of the vehicle.

[0040] In the diagram: 1-Inlet grille; 2-Vector nozzle; 3-Propulsion motor; 4-Support bearing; 5-Dynamic seal; 6-Main shaft; 7-Positioning guide cone; 8-Impeller; 9-Locking nut; 10-Water-lubricated bearing; 11-Guide vane; 12-Nozzle rotary bearing; 13-Flow channel; 14-Drive gear; 15-Nozzle servo motor. Detailed Implementation

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] It should be noted that, unless otherwise specified, the features in the following embodiments and implementation methods can be combined with each other.

[0043] like Figure 1 As shown, the hull of the vehicle is a rotating shell formed by rotating about the longitudinal axis Z, and its outer surface is defined as the nominal outer envelope of the hull. The internal underwater propulsion of this embodiment includes four flow channels 13 installed inside the vehicle and a propulsion unit disposed in each flow channel 13.

[0044] The propulsion unit includes a propulsion motor 3, a main shaft 6, a support bearing 4, a dynamic seal 5, a water-lubricated bearing 10, an impeller 8, a guide vane 11, a vector nozzle 2, and a nozzle servo motor 15.

[0045] 1. Flow channel and inlet grille.

[0046] The flow channel 13 is a closed shell structure, forming a water flow channel inside. Its front end is sealed to the water inlet opening on the shell via a flange, and an inlet grille 1 is fixedly installed at the water inlet opening. The inlet grille 1 consists of several radially and circumferentially interwoven grille bars, forming a mesh structure to block aquatic plants, floating objects, and other debris from entering the propeller. The incoming flow edge of each grille bar adopts a rounded transition and a streamlined cross-section to reduce disturbance to the incoming water flow field and energy loss. The inlet section of the flow channel is a contraction section, which contracts and accelerates the incoming flow passing through the grille, causing it to enter the impeller inlet area with a nearly uniform axial velocity.

[0047] 2. Impeller, guide vane and shaft support.

[0048] The propulsion motor 3 is fixed in the middle section of the flow passage by flange, and connected with the main shaft 6 by coupling. The dynamic seal 5 is arranged between the propulsion motor and the main shaft, for preventing the external water from entering the motor. The front end of the main shaft 6 is supported by the support bearing 4, and the rear end is supported by the water-lubricated bearing 10, so as to keep the impeller position stable in axial and radial directions. The support bearing 4 is selected from an angular contact ball bearing or a tapered roller bearing, which can bear the axial thrust generated by the impeller and the radial load. The bearing bush of the water-lubricated bearing 10 is made of wear-resistant polymer material, and the inner surface is provided with a spiral water groove, so as to form a stable water film under the action of water flow, realize oil-free lubrication and carry away the friction heat.

[0049] The impeller 8 is installed at the rear end of the main shaft, connected by key and axially fixed by the lock nut 9. The impeller 8 is an axial flow impeller, which adopts lift-type airfoil blades, and the blades are twistedly distributed along the radial direction to adapt to the local speed triangle. In the embodiment, the number of blades is 4, and the diameter of the impeller is about 99%-99.5% of the diameter of the flow passage, so as to balance the propulsion efficiency and cavitation performance.

[0050] The guide vane 11 is fixed in the flow passage and located behind the impeller 8, forming a ring-shaped guide vane assembly. The number of guide vane blades is 6, and the inlet edge angle of the guide vane is matched with the absolute velocity direction of the outlet of the impeller, for eliminating the water flow rotation component, converting more rotary kinetic energy into axial kinetic energy, so as to improve the overall propulsion efficiency and improve the subsequent flow passage flow field.

[0051] The propulsion motor 3 is a water-lubricated permanent magnet synchronous motor, which adopts a shielded or oil-filled structure, so as to improve the operation reliability of the motor in the underwater high-pressure environment.

[0052] 3. The flow passage bending section and the conformal vector nozzle.

[0053] Downstream of the guide vane 11, the flow passage 13 gradually bends and transitions to the vector nozzle 2 at the side wall of the shell, forming an outlet bending section, which is nearly axial to the longitudinal axis of the vehicle at an angle of 10°-20°. The curvature and cross-sectional shape of the bending section are optimized by CFD, so that the water flow can keep attached flow as much as possible during the bending process, and avoid strong separation and energy loss.

[0054] The outlet bending section ends at the annular mounting opening on the side wall of the vehicle shell, and the boundary line of the opening is a closed curve formed by the intersection of the nominal envelope surface of the shell and a toroidal surface.

[0055] As Figure 3As shown, a low-drag conformal vector nozzle 2 is installed at this annular opening, with its body in a horn-shaped revolution structure, its outer surface generated by rotating a horn-shaped generatrix around the longitudinal axis of the vehicle, and continuously connected with the generatrix of the vehicle shell, forming a rotatable shell segment of the hull shell after installation. The inner cavity of the nozzle is in communication with the outlet bending flow passage, and the cross section of the inner cavity gradually expands from approximately circular to horn-shaped, so as to improve the jet diffusion and reduce reflection.

[0056] The first derivative of the outer surface of the nozzle and the outer surface of the shell is continuous at the connection, and preferably the second derivative is also continuous, so as to ensure that the outer shape is geometrically smooth when the nozzle is in the first working position and the second working position, and no obvious break lines or corner points are generated.

[0057] As shown in Figure 4 (a) When the vector nozzle 2 is in the first working position, its jet direction points to the stern of the vehicle, the phase angle of the vector nozzle is 0°, the outer surface of the vector nozzle 2 conforms to the nominal outer envelope surface, and is geometrically continuous in the normal direction at the connection with the adjacent shell; (b) When the vector nozzle 2 is in the second working position, its jet direction points to the bow of the vehicle, the phase angle of the vector nozzle is 180°, and the outer surface of the vector nozzle 2 also conforms to the nominal outer envelope surface.

[0058] The vector nozzle 2 can rotate around its own axis from the first working position to the second working position, and continuously rotate within the range of the vector working positions between the two. When the nozzle rotates around its own axis between the two working positions to other vector working positions, the outer surface of the nozzle allows a limited local deviation relative to the nominal outer envelope surface of the hull, and the amount of local protrusion or depression is constrained within a predetermined limit, so as to minimize the additional resistance caused by the sudden change of the outer shape while ensuring the vector thrust capacity.

[0059] In a preferred embodiment, the maximum radial deviation of the vector nozzle 2 relative to the nominal outer envelope surface in the non-first / second working position is not more than 5% to 10% of the radius of the shell at this position, preferably not more than 5%, so as to ensure that the nozzle does not form a local step or sharp protrusion that significantly affects the propulsion efficiency when the nozzle is deflected.

[0060] 4. Nozzle rotation support and driving mechanism.

[0061] As shown in Figure 2 The vector nozzle 2 is connected with the shell or the load-bearing ring structure through a nozzle rotation bearing 12. The nozzle rotation bearing 12 is a cross-roller bearing, the outer ring of which is fixed on the shell or the fixed seat, and the inner ring is connected with the nozzle body, so that the nozzle can freely rotate around its own axis by 360°. The rollers in the cross-roller bearing are arranged at 90°, and can simultaneously bear radial, axial and overturning moments, so as to realize high stiffness support.

[0062] Preferably, the nozzle rotating bearing 12 is arranged along the circumference of the vector nozzle 2 and cooperates with an integral gear ring arranged on the outer circumference of the vector nozzle 2 to form a load-bearing and transmission integrated structure for transmitting the output torque of the nozzle servo motor 15 to the vector nozzle 2 while supporting the rotation of the vector nozzle 2 about its own axis.

[0063] The outer circumference of the nozzle is machined with an integrally formed gear ring, and the nozzle servo motor 15 is fixed in the housing through a mounting seat, with its output shaft connected to the drive gear 14. The drive gear 14 meshes with the nozzle gear ring, thereby transmitting the torque output by the servo motor to the nozzle to achieve the rotation of the nozzle. The servo motor is selected to have fast response speed and high angular control accuracy, and the nozzle angle is closed-loop controlled through an encoder or angle sensor.

[0064] The nozzle servo motor 15 is a high-torque, high-response-speed servo motor equipped with an angle sensor for closed-loop control of the rotation angle of the vector nozzle 2 to achieve accurate adjustment of the thrust direction.

[0065] 5. Propulsion and vector control working process.

[0066] The propulsion motor 3 is connected to the impeller 8 through the main shaft 6, and the main shaft 6 is forwardly and rearwardly supported and positioned by the support bearing 4 and the water-lubricated bearing 10. The guide vane 11 is used to eliminate the rotational component of the water flow discharged by the impeller 8, so that the water flow enters the outlet bend section in a nearly axial direction.

[0067] After the propulsion motor 3 is started to drive the impeller 8 to rotate, the water flow enters the flow passage 13 through the inlet grille 1 and tends to be uniformly axial under the action of the positioning flow cone 7, enters the impeller 8 to be accelerated, then passes through the guide vane 11 to be rectified and flows along the outlet bend section to the inner cavity of the vector nozzle 2, and finally is sprayed out of the nozzle to form a high-speed jet flow to generate thrust.

[0068] When the nozzle is directed towards the stern of the vehicle (denoted as nozzle phase angle 0°), the jet flow is roughly along the -Z axis direction, generating forward thrust of the vehicle (as shown in Figure 5 ).

[0069] When the nozzle is rotated by 180° and directed towards the bow of the vehicle (nozzle phase angle 180°), the jet flow is sprayed along the +Z axis direction, generating reverse thrust, which can be used for vehicle backward movement or emergency braking (as shown in Figure 6 ).

[0070] When the nozzle is deflected to point upwards or downwards, the jet flow generates a component in the X direction, which can be used for vehicle upward or downward movement (as shown in Figure 7 ). Figure 8 When the nozzle is deflected to point sideways, the jet flow generates a component in the Y direction, which can be used for vehicle lateral movement (as shown in . .

[0071] By arranging multiple thruster units at bow, stern and sides respectively, and coordinating the jet angle and thrust size, complex maneuvering combinations can be achieved in three-axis translation and three-axis rotation, for example: Two thrusters with reverse deflection jets can combine to generate pure torque, enabling zero-radius turning in place. Different deflection angle combinations of bow and stern thrusters can enable lateral translation of the vehicle while maintaining its attitude. By periodically changing the jet angle at a certain angular velocity, the vehicle can achieve periodic oscillation or rotation around a fixed point, etc.

[0072] Further, the control system is electrically connected to each thruster motor 3 and jet servo motor 15, and is configured to control the thrust size and vector jet 2 pointing angle of each thruster, enabling the underwater vehicle to perform attitude and trajectory control in six degrees of freedom, including forward, backward, upward, downward, lateral translation, and pitch, yaw, roll.

[0073] The control system can be configured to deflect the vector jets 2 of at least two thrusters to have substantially the same size but opposite directions of jet flow pointing angles, and control the corresponding thruster motors 3 to output thrusts of substantially the same size but opposite directions, to combine to generate an approximate pure torque about the vehicle's center of mass, thereby enabling the vehicle to turn in place with zero radius.

[0074] Alternatively, the control system is configured to control the thrusters arranged at the bow and stern to work cooperatively, deflect the vector jets 2 of each thruster to different pointing angle combinations, and enable the thrust components of each thruster jet in the lateral direction to add up in the same direction while maintaining the vehicle's attitude substantially unchanged, thereby enabling the vehicle to move in the lateral direction.

[0075] Based on the embodiments of the present application, further noise reduction design and material selection are described.

[0076] The flow channel 13 shell is made of carbon fiber reinforced composite material, which has high stiffness, low density and excellent corrosion resistance. A layer of porous sound-absorbing material (porous rubber-based material or porous polyurethane material) is attached to the inner wall of the flow channel, and its thickness and pore size distribution are optimized for the main noise frequency band of the impeller to improve the absorption efficiency of impeller noise and flow noise. With the geometric cooperation of the conformal shell, the increase in vortex-induced noise caused by local protrusions and recesses is avoided, and the integration of low noise and low resistance is achieved.

[0077] The thruster motor 3 can adopt a shielded or oil-filled structure to further increase the sealing and pressure resistance of the motor cavity, reduce the dependence on dynamic seals, and facilitate long-term reliable operation at great depths.

[0078] The above embodiments can be modified in various ways without departing from the concept of the present application: The nozzle rotating bearing 12 can be replaced by a four-point contact ball bearing, a three-row roller bearing, etc., as long as it can bear the combined load in the working state of the nozzle and realize 360° continuous rotation. In addition to the servo motor + gear transmission, the nozzle driving mechanism can also use a ring torque motor to directly drive the nozzle, or use a worm gear mechanism to obtain self-locking function. The propulsion motor can use a permanent magnet synchronous motor, an asynchronous motor or a water turbine to drive, as long as it can be reliably connected with the main shaft and meet the output power requirement. In addition to composite materials, the flow channel shell can also use aluminum alloy, stainless steel or titanium alloy, etc. The inner wall can form a sound absorption layer by pasting or pouring.

[0079] These modifications are all routine design adjustments that can be made by those skilled in the art after reading the present application, and should be included in the protection scope of the present application.

[0080] The above embodiments have described the technical solutions and beneficial effects of the present application in detail. It should be understood that the above description is only a specific embodiment of the present application and is not intended to limit the present application. Any modification, supplement and equivalent replacement made within the principle scope of the present application should be included in the protection scope of the present application.

Claims

1. A built-in underwater propulsion device with a conformal vector nozzle, characterized in that, Includes multiple flow channels (13) installed inside the aircraft and a thruster unit disposed in each flow channel (13); The flow channel (13) includes an inlet section, an impeller section, a guide vane section, and an outlet bend section; the inlet section is connected to the water outside the vehicle and is equipped with an inlet grille (1); The thruster unit includes a propulsion motor (3) and an impeller (8) in the impeller section, a guide vane (11) in the guide vane section, a vector nozzle (12) installed in the outlet bend section, and a nozzle servo motor (15) for driving the vector nozzle (12) to rotate. The vector nozzle (12) is a horn-shaped rotating body that constitutes a rotatable segment of the aircraft hull. When the vector nozzle (12) is in the first working position with a rotation of 0° and the second working position with a rotation of 180°, the outer surface of the vector nozzle (12) conformally fits the outer envelope surface of the aircraft, and the angle between the nozzle outlet direction of the vector nozzle (12) and the axis of the aircraft is 10°~20°. When the vector nozzle (12) is in other working positions, the maximum radial deviation of the outer surface of the vector nozzle (2) relative to the outer envelope surface of the aircraft does not exceed 10% of the radius of the aircraft hull at that location.

2. The built-in underwater thruster with a conformal vector nozzle according to claim 1, characterized in that, The vector nozzle (2) is connected to a fixed support structure provided on the aircraft hull or flow channel (13) via a nozzle rotary bearing (12); The output shaft of the nozzle servo motor (15) is connected to the drive gear (14), which meshes with the gear ring on the outer circumference of the vector nozzle (2). Under the drive of the nozzle servo motor (15), the vector nozzle (2) achieves controlled rotation around its own axis.

3. The built-in underwater thruster with a conformal vector nozzle according to claim 1, characterized in that, The maximum radial deviation of the outer surface of the vector nozzle (2) relative to the outer envelope of the vehicle does not exceed 5% of the radius of the vehicle hull at that location.

4. The built-in underwater thruster with a conformal vector nozzle according to claim 1, characterized in that, When the vector nozzle (2) is in the first working position, its nozzle outflow direction points towards the stern of the vehicle; when the vector nozzle (2) is in the second working position, its nozzle outflow direction points towards the bow of the vehicle.

5. The built-in underwater thruster with a conformal vector nozzle according to claim 1, characterized in that, The flow channel (13) is made of composite material or corrosion-resistant metal material, and its inner wall is attached with a porous sound-absorbing material layer to absorb the noise generated by the impeller (8) and turbulence.

6. The built-in underwater thruster with a conformal vector nozzle according to claim 1, characterized in that, The propulsion motor (3) is connected to the impeller (8) via the main shaft (6), and the main shaft (6) is supported and positioned by the support bearing (4) and the water-lubricated bearing (10).

7. The built-in underwater thruster with a conformal vector nozzle according to claim 6, characterized in that, The propulsion motor (3) is connected to the main shaft (6) through a dynamic seal (5). The dynamic seal (5) adopts a multi-stage sealing structure, including an elastic sealing ring, a rigid retaining ring, and a sealing cavity filled with grease, which is used to prevent water from entering the propulsion motor (3).

8. The built-in underwater thruster with a conformal vector nozzle according to claim 1, characterized in that, The guide vane (11) includes several guide vanes evenly arranged on the annular guide vane ring; the inlet edge angle of the guide vane matches the flow velocity direction of the water flow at the outlet of the impeller (8) to eliminate the rotation component of the water flow discharged from the impeller (8) so that the water flow enters the outlet bend section in a direction close to the axial direction.

9. The built-in underwater thruster with a conformal vector nozzle according to claim 1, characterized in that, The inlet section of the flow channel (13) is a contraction section, which is used to contract and accelerate the water flow passing through the inlet grille (1); The impeller section and guide vane section are straight pipe sections with equal cross-sections; the outlet bend section is a bend section with a continuous change in curvature, the curvature of which is monotonically or gradually changes along the flow direction, so that the water flow maintains attached flow and reduces local energy loss during the bend.

10. The built-in underwater thruster with a conformal vector nozzle according to claim 1, characterized in that, The aircraft has four flow channels (13) inside, two of which are located opposite each other at the front of the aircraft and the other two are located opposite each other at the rear of the aircraft. The propulsion motor (3) and nozzle servo motor (15) in each flow channel are connected to the control system. The control system controls the thrust of each propulsion motor (3) and the pointing angle of the vector nozzle (2) to enable the underwater vehicle to achieve attitude and trajectory control of forward, backward, surfacing, diving, lateral movement, pitching, yaw and roll.

Images