Vehicle-mounted multi-duct underwater propeller

Abstract

The vehicle-mounted multi-duct underwater propeller comprises a pipe body and a rotor, and a first duct and a second duct which are communicated with each other are arranged in the pipe body; in the direction from the first duct to the second duct, the inner diameter of the first duct is gradually increased from the end, away from the second duct, of the first duct to the end, close to the second duct, of the first duct; the rotor is rotationally arranged in the water inlet end of the second duct. By additionally arranging the first duct and the second duct, water flow is guided to be sprayed out from a specific outlet, and it is guaranteed that the propeller can be applied to a vehicle. The inner diameter of the first duct is gradually increased from the end away from the second duct to the end close to the second duct, so that water flow is gradually decelerated, the inlet pressure of the rotor is increased, and the rotor is assisted to avoid cavitation. And by reducing the chord length, reducing the load of a low-pressure area, unloading the low-pressure area of the rotor and increasing the pressure of the low-pressure area, the cavitation phenomenon generated when the pressure is lower than medium saturated vapor pressure is avoided, and the working efficiency of the propeller is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of underwater propellers, and in particular relates to a vehicle-mounted multi-duct underwater propeller. Background Art

[0002] In recent years, abnormal global climate change has led to an increase in the frequency and intensity of floods. In cities, heavy rains often cause waterlogging, and roads are flooded. Once ordinary vehicles enter areas with deep water, they are easily trapped in the water due to water ingress into the engine and loss of grip on the wheels, which seriously affects the normal travel of people and the development of rescue work. In rural and other wild areas, when floods strike, many vehicles are also trapped, leaving drivers and passengers waiting for rescue, which poses many safety hazards. This kind of flood and waterlogging scene urgently needs a device that can help vehicles get out of the water, and vehicle-mounted thrusters came into being.

[0003] On the other hand, with the improvement of people's living standards, more and more outdoor enthusiasts are keen on outdoor adventure activities. It is common to drive across rivers and pass through muddy and flooded roads. However, these complex wading conditions often exceed the normal traffic capacity of vehicles. The wheels are easily sunk into the water or stuck by underwater debris, causing the vehicle to be trapped. At this time, the vehicle-mounted thruster can be used as a powerful auxiliary tool to help the vehicle pass these wading areas smoothly, and the adventure journey goes smoothly, meeting people's needs to continuously expand the scope of outdoor activities.

[0004] With the continuous development of modern automobile manufacturing technology, the vehicle structure design, parts manufacturing and overall performance have been greatly improved, which provides a good foundation for the installation and integration of vehicle-mounted thrusters. On the one hand, a certain amount of space and suitable carrying capacity are reserved on the car to facilitate the installation of thrusters and their supporting equipment; on the other hand, the automobile modification industry is becoming more and more mature, with professional installation and debugging technology and experience, which can reasonably install vehicle-mounted thrusters on different types of vehicles and ensure their compatibility with the original systems of the vehicle (such as electrical systems, control systems, etc.), so that the thrusters can play their role safely and effectively.

[0005] Existing thrusters are mainly used in ships. When the underwater thrusters suitable for ships are reduced in size and applied to vehicles, they cannot be directly applied to vehicles because they mainly rely on blades to achieve propulsion under trees. In addition, due to the limited size of the vehicle body, the rotor in the thruster is smaller in size, and high-speed rotors are prone to cavitation problems. The vehicle body size limits the inclination angle of the first duct to be too small, all of which lead to low efficiency of the underwater thruster. Summary of the invention

[0006] The purpose of the present invention is to provide a vehicle-mounted multi-duct underwater thruster to solve the problems existing in the above-mentioned prior art.

[0007] To achieve the above object, the present invention provides a vehicle-mounted multi-duct underwater thruster, comprising: A tube body, wherein a first duct and a second duct are arranged inside the tube body and are in communication with each other; in a direction from the first duct to the second duct, an inner diameter of the first duct gradually increases from an end thereof away from the second duct to an end thereof close to the second duct; A rotor, wherein the rotor is rotatably arranged inside the water inlet end of the second duct, and the blade chord length of the rotor is: Where: l is the chord length; x is selected in the range of 0.8-1.2; D is the rotor diameter; Z is the number of rotor blades; is the rotor hub diameter.

[0008] Optionally, the inner contour of the first duct extends from an end thereof away from the second duct toward an end thereof close to the second duct along a preset curve contour, wherein the preset curve contour is formed by connecting two Bezier curves with straight line tangent constraints set between the two Bezier curves; The area of ​​the first duct close to the center of the curve contour is the first area, and the area of ​​the first duct far from the center of the curve contour is the second area. The angle between the straight line and the tangent of the Bezier curve in the first area is greater than the angle between the straight line and the tangent of the Bezier curve in the second area.

[0009] Optionally, an included angle between the straight line in the first duct and the tangent line of the Bezier curve is between 10° and 65°.

[0010] Optionally, the blade density of the rotor blades is between 0.5 and 0.7.

[0011] Optionally, the inner contour of the second duct extends from an end thereof close to the first duct toward an end thereof away from the first duct along a bilinic curve, and the bilinic curve is: The intersection of the second duct near the first duct end surface and the second duct axis is the central origin, the x-axis is arranged from the origin along the second duct axis, and the y-axis is arranged from the origin along the radial line of the second duct near the first duct end surface; a is the maximum value of the horizontal coordinate x; Furthermore, an end surface of the second duct facing away from the first duct satisfies: .

[0012] Optionally, an end surface of the second duct facing away from the first duct adopts any one of a circular nozzle, an elliptical nozzle or a U-shaped nozzle.

[0013] Optionally, an end of the first duct away from the second duct is a smooth chamfered structure.

[0014] Compared with the prior art, the present invention has the following advantages and technical effects: In the present invention, due to the suction effect of the rotor, water flows into the first duct or the second duct, and the water flows out through the other duct after the acceleration effect of the rotor. The high-speed water flows provide a reaction force for the vehicle and generate thrust. The present invention guides the water flow to be ejected from a specific outlet by adding the first duct and the second duct structure, thereby ensuring that the propeller can be used in the vehicle.

[0015] In the present invention, the inner diameter of the first duct gradually increases from the end away from the second duct to the end close to the second duct, forming a gradually expanding structure, so that the water flow gradually slows down and increases the rotor inlet pressure, thereby assisting the rotor in avoiding cavitation. The present invention reduces the chord length, reduces the load in the low-pressure area, unloads the low-pressure area of ​​the rotor, increases the pressure in the low-pressure area, avoids cavitation caused by the pressure being lower than the saturated vapor pressure of the medium, and improves the working efficiency of the propeller; and there is no low thrust caused by cavitation, cavitation damage to the rotor blades, high noise, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 It is a schematic diagram of the structure of the vehicle-mounted multi-duct underwater propulsor of the present invention; Figure 2 It is a schematic diagram of the first duct structure of the present invention; Figure 3 This is a schematic diagram of the rotor structure of the present invention; Figure 4 This is a schematic diagram of the stator structure of the present invention; Figure 5 This is a diagram of rotor cavitation in the prior art; Figure 6 This is a diagram of the rotor cavitation situation of the present invention; Figure 7 This is the duct pressure field diagram of the present invention; Figure 8 This is the streamline diagram of the second duct system of the stator of the present invention.

[0018] Among them, 1 is a tube body, 2 is a first duct, 3 is a second duct, 4 is a rotor, and 5 is a stator. DETAILED DESCRIPTION

[0019] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. The present invention will be described in detail below with reference to the drawings and in combination with the embodiments.

[0020] like Figure 1-Figure 4 As shown, this embodiment provides a vehicle-mounted multi-duct underwater propulsion device, including a tube body 1 and a rotor 4. A first duct 2 and a second duct 3 are arranged inside the tube body 1, which are connected to each other; from the first duct 2 to the second duct 3, the inner diameter of the first duct 2 gradually increases from the end away from the second duct 3 to the end close to the second duct 3; the rotor 4 is rotatably arranged inside the water-entering end of the second duct 3, and the blade chord length of the rotor 4 is: Where: l is the chord length; x is selected in the range of 0.8-1.2; D is the diameter of the rotor 4; Z is the number of rotor 4 blades; is the hub diameter of rotor 4.

[0021] The present invention has two working conditions:

[0022] First working condition: the first duct 2 is the water inlet duct, the second duct 3 is the water outlet duct, the end of the first duct 2 away from the second duct 3 is the water inlet end, and the end of the second duct 3 away from the first duct 2 is the water outlet end. In the present invention, due to the suction effect of the rotor 4, the water flows into the water inlet end of the first duct 2, and the water flows through the water outlet end of the second duct 3 after the acceleration effect of the rotor 4. The high-speed water flow provides a reaction force for the vehicle and generates thrust.

[0023] The second working condition: the second duct 3 is the water inlet duct, the first duct 2 is the water outlet duct, the end of the first duct 2 away from the second duct 3 is the water outlet, and the end of the second duct 3 away from the first duct 2 is the water inlet. In the present invention, due to the suction effect of the rotor 4, the water flows into the water inlet end of the second duct 3, and the water flows through the water outlet end of the first duct 2 after the acceleration effect of the rotor 4. The high-speed sprayed water provides a reaction force for the vehicle and generates thrust. The reversing function is realized. The present invention guides the water flow to be sprayed from a specific outlet by adding the first duct 2 and the second duct 3 structure, ensuring that the propeller can be used in the vehicle.

[0024] In the present invention, from the first duct 2 to the second duct 3, the inner diameter of the first duct 2 gradually increases from the end away from the second duct 3 to the end close to the second duct 3, forming a gradually expanding structure, so that the water flow gradually slows down and increases the inlet pressure of the rotor 4, and assists the rotor 4 to avoid cavitation. The water flow enters the rotor 4 area from the first duct 2, and the clockwise rotation of the rotor 4 from left to right is positive. The fluid medium is accelerated by the pressure difference between the front and rear of the rotor 4 blades. At the same time, due to the high-speed rotation of the rotor 4, the water flow is also given a circumferential velocity. When the pressure is lower than the saturated vapor pressure of the medium, cavitation will occur. The present invention limits the blade chord length, reduces the chord length within a certain range, reduces the load of the low-pressure area, unloads the low-pressure area of ​​the rotor 4, increases the pressure of the low-pressure area, avoids the pressure lower than the saturated vapor pressure of the medium to cause cavitation, and improves the working efficiency of the propeller; and there is no low thrust caused by cavitation, cavitation damage of the rotor 4 blades, high noise, etc.

[0025] At the same time, the first duct 2 and the second duct 3 are smoothly connected, the rotor 4 is rotatably arranged inside the water inlet end of the second duct 3 and is coaxial with the parallel section of the second duct 3, and the rotation of the rotor 4 is controlled by a driving mechanism, which is a prior art and will not be described again.

[0026] A further optimization scheme is that the inner contour of the first duct 2 extends along a preset curve contour from the end thereof facing away from the second duct 3 toward the end close to the second duct 3, and the preset curve contour is formed by connecting two Bezier curves with straight lines set on the two Bezier curves by tangent constraints; the area of ​​the first duct 2 close to the center of the curve contour is the first area, and the area of ​​the first duct 2 away from the center of the curve contour is the second area, and the angle between the straight line and the tangent of the Bezier curve in the first area is greater than the angle between the straight line and the tangent of the Bezier curve in the second area.

[0027] The inner contour of the first duct 2 extends along the preset curve contour, which is formed by connecting two Bezier curves with straight lines set on the two Bezier curves by tangent constraints. The total length, height and other structural parameters depend on the vehicle space. The area of ​​the first duct 2 close to the center of the curve contour is the first area, and the area of ​​the first duct 2 far from the center of the curve contour is the second area; the first area is a high inflow area, that is, the fluid entering the first area has a fast speed and a large flow rate, and the second area is a low inflow area. Compared with the fluid flow rate and flow rate of the first area, the fluid flow rate entering the second area is slower and the flow rate is smaller; the angle between the straight line and the Bezier curve tangent in the first area is greater than the angle between the straight line and the Bezier curve tangent in the second area. Under the premise of ensuring the spatial size, the phenomenon of flow separation of the water flow is avoided, the flow loss is reduced, and the efficiency is improved. The linear transition of the outer contour of the first duct 2 is good, and the overall propulsion efficiency is higher. The Bezier curve in this embodiment is a high-order Bezier curve, and the high order refers to the order above the second power, which further controls the shape of the inner contour of the first duct 2, reduces the flow loss, and improves the efficiency.

[0028] Further optimization scheme, the angle between the straight line and the tangent line of the Bezier curve in the first duct 2 is between 10° and 65°. Under the premise of ensuring the space size, the flow separation of water flow is avoided and the flow loss is reduced.

[0029] In a further optimized solution, the blade density of the rotor 4 blades is between 0.5 and 0.7. Under the premise of ensuring the normal operation of the rotor 4, the present invention combines the reduction of the blade density and the blade chord length to increase the pressure in the low-pressure area and prevent cavitation.

[0030] According to a further optimization scheme, the inner contour of the second duct 3 extends from its end close to the first duct 2 to its end away from the first duct 2 along a double-negative curve, and the double-negative curve is: The intersection of the end surface of the second duct 3 close to the first duct 2 and the axis of the second duct 3 is the central origin, the x-axis is arranged from the origin along the axis of the second duct 3, and the y-axis is arranged from the origin along the radial line of the second duct 3 close to the end surface of the first duct 2; a is the maximum value of the horizontal coordinate x; Furthermore, the end surface of the second duct 3 away from the first duct 2 satisfies: .

[0031] The outer contour line of the second duct 3 of the present invention is a hyperbola. The structural parameters of the second duct 3 are determined according to the rear space of the vehicle. The nonlinear contraction structure of the hyperbola is followed from the water inlet end to the water outlet end. The hyperbola distribution parameters are optimized to avoid flow loss. After the water flows through the stator 5 area, it is gradually accelerated to eject to improve the overall thrust.

[0032] Preferably, the present invention further includes a stator 5, which is fixedly arranged inside the second duct 3 and arranged at the outlet end of the second duct 3, and the stator 5 and the tail of the second duct 3 are an integrated structure. After the water flows through the rotor 4 area, it is rectified and ejected from the second duct 3 through the stator 5 structure, and the high-speed ejected water flow provides a reaction force for the vehicle and generates thrust. In this process, the high-speed rotating wake after the action of the rotor 4 enters the stator 5 area, and the non-axial speed causes thrust loss. The stator 5 of the present invention adopts a three-dimensional structural inverse design method, abandons the traditional NACA66 airfoil structure, and redesigns the bone line of the stator 5 with different radius sections, including single-reduced linear attack angle, nonlinear chord length, nonlinear camber and other parameters, so that it can maximize the recovery of the useless work of the wake and improve the overall propulsion efficiency. The simulation method is used to obtain the speed of the water flow after passing through the rotor 4 and the axial and circumferential velocity components, and the parameters such as the stator 5 safety angle and camber are calculated to obtain the stator 5 structure adapted to the vehicle-mounted propeller. The advantage is that the ability to balance the non-axial velocity component of the wake is strong, and the overall propulsion efficiency is higher.

[0033] In a further optimized solution, the end face of the second duct 3 away from the first duct 2 adopts any one of a circular nozzle, an elliptical nozzle or a U-shaped nozzle. The port of the second duct 3 of different shapes is selected according to different requirements of the rear of the vehicle.

[0034] To further optimize the solution, the end of the first duct 2 away from the second duct 3 has a smooth chamfer structure to avoid excessive instantaneous curvature value affecting the near flow.

[0035] like Figure 5 and Figure 6 As shown, Figure 5 This is a diagram of the cavitation condition of the rotor 4 in the prior art; Figure 6 This is a diagram of the cavitation situation of the rotor 4 of the present invention; after adopting the rotor 4 of this solution, the low-pressure area of ​​the rotor 4 with the same speed and size is greatly reduced, from 60% to 1%, and cavitation is suppressed.

[0036] like Figure 7 and Figure 8 As shown, Figure 7 This is the duct pressure field diagram of the present invention; Figure 8 This is the streamline diagram of the stator 5 and the second duct 3 system of the present invention. After the present invention adopts the water inlet duct and the second duct 3 of the technical solution, there is no obvious low-pressure area in the duct as a whole. The water flows through the stator 5 to integrate the non-axial velocity components and convert them into axial axial velocity. The streamline of the ejected medium is regular and almost an axial straight line. The stator 5 and the duct work together to greatly improve the overall propulsion efficiency under the same thrust.

[0037] The description of the above embodiments is only used to help understand the method of the present application and its core idea; at the same time, for a person skilled in the art, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

[0038] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0039] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0040] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A vehicle-mounted multi-duct underwater propulsion device, characterized in that: include: A tube body (1), wherein a first duct (2) and a second duct (3) which are in communication with each other are arranged inside the tube body (1); in a direction from the first duct (2) toward the second duct (3), the inner diameter of the first duct (2) gradually increases from an end thereof which is away from the second duct (3) toward an end thereof which is close to the second duct (3); A rotor (4), the rotor (4) being rotatably disposed inside the water inlet end of the second duct (3), and the blade chord length of the rotor (4) being: Wherein: l is the chord length; x is selected in the range of 0.8-1.2; D is the diameter of the rotor (4); Z is the number of blades of the rotor (4); is the hub diameter of the rotor (4).

2. The vehicle-mounted multi-duct underwater propulsion device according to claim 1, characterized in that: The inner contour of the first duct (2) extends from an end thereof facing away from the second duct (3) toward an end thereof close to the second duct (3) along a preset curve contour, wherein the preset curve contour is formed by connecting two Bezier curves with straight line tangent constraints set on the two Bezier curves; The area of ​​the first duct (2) close to the center of the curve contour is the first area, and the area of ​​the first duct (2) far from the center of the curve contour is the second area. The angle between the straight line and the tangent of the Bezier curve in the first area is greater than the angle between the straight line and the tangent of the Bezier curve in the second area.

3. The vehicle-mounted multi-duct underwater propulsion device according to claim 2, characterized in that: The angle between the straight line in the first duct (2) and the tangent line of the Bezier curve is between 10° and 65°.

4. The vehicle-mounted multi-ducted underwater propulsion device according to claim 1, characterized in that: The blade density of the rotor (4) blades is between 0.5 and 0.

7.

5. The vehicle-mounted multi-ducted underwater propulsion device according to claim 1, characterized in that: The inner contour of the second duct (3) extends from an end thereof close to the first duct (2) to an end thereof away from the first duct (2) along a double-knotted curve, wherein the double-knotted curve is: The intersection of the end surface of the second duct (3) close to the first duct (2) and the axis of the second duct (3) is the central origin, the x-axis is arranged from the origin along the axis of the second duct (3), and the y-axis is arranged from the origin along the radial line of the second duct (3) close to the end surface of the first duct (2); a is the maximum value of the horizontal coordinate x; Furthermore, an end surface of the second duct (3) facing away from the first duct (2) satisfies: 。 6. The vehicle-mounted multi-ducted underwater propulsion device according to claim 5, characterized in that: An end surface of the second duct (3) facing away from the first duct (2) adopts any one of a circular nozzle, an elliptical nozzle or a U-shaped nozzle.

7. The vehicle-mounted multi-ducted underwater propulsion device according to claim 1, characterized in that: An end of the first duct (2) facing away from the second duct (3) is a smooth chamfered structure.

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