Super-cavitation vehicle high-speed water entry buffer head cap
By setting up positioning components and energy-absorbing components of gradually increasing density foam plastic bodies inside the supercavitating hull fairing, the problems of unstable connection between the buffer cap and the hull and insufficient absorption of impact energy were solved, achieving stable water entry and effective buffering.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- NORTHWESTERN POLYTECHNICAL UNIV
- Filing Date
- 2023-08-16
- Publication Date
- 2026-07-07
AI Technical Summary
When a traditional supercavitating vehicle enters the water at high speed, the connection between the buffer cap and the vehicle is unstable, which causes radial vibration caused by aerodynamic loads, affecting the load reduction effect and attitude position. In addition, the existing buffer device has insufficient structural strength and is difficult to effectively absorb the impact energy of entering the water.
The system employs a positioning component and an energy-absorbing component consisting of gradually increasing density foam plastic bodies inside the flow guide. The positioning component secures the flow guide through an arc-shaped plate and connectors, while the foam plastic bodies sequentially absorb impact energy, preventing vibration and reducing impact force.
It achieves a stable connection between the buffer cap and the hull, reduces attitude deviation during water entry, effectively absorbs impact energy, and ensures the safety of the linkage structure and the load reduction effect.
Smart Images
Figure CN117190800B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of high-speed water entry buffer and load reduction for supercavitating vessels, specifically to a high-speed water entry buffer cap for supercavitating vessels. Background Technology
[0002] With the continuous advancement of military technology, the demand for speed in underwater weaponry has increased. Supercavitating vehicles, by ejecting high-temperature exhaust gases from their noses, completely envelop the vehicle, transforming the navigation environment from water to gas, significantly reducing drag and increasing speed. Simultaneously, rocket-assisted launch technology and aircraft-drop technology are maturing, and researchers are experimenting with rocket-assisted delivery of supercavitating vehicles, further enhancing their penetration capabilities.
[0003] Because supercavitating vehicles navigate in a gaseous environment, traditional fin rudders are inefficient for maneuvering. Therefore, heading is typically controlled by a tail-mounted rocket engine changing thrust or by a cavitation generator at the nose. When a supercavitating vehicle is combined with rocket-assisted flight technology, it undergoes a high-speed water entry phase during the transition from an airborne to an underwater trajectory. During this phase, the surrounding medium changes from less dense air to denser water, subjecting the supercavitating vehicle to immense impact loads. These loads, acting on the cavitation generator at the nose, can easily damage the linkage mechanism used for deflection, rendering the vehicle inoperable after water entry. Therefore, appropriate buffering and load reduction measures are necessary to ensure the safety of the supercavitating vehicle during its high-speed water entry.
[0004] The existing buffer head cap mainly consists of a fairing, a buffer energy absorption device, and a limiting and disengaging mechanism. The fairing structure can move back and forth along the axial direction of the vehicle to adapt to the needs of different stages of the vehicle's movement. During water entry, the telescopic rod in the buffer energy absorption device absorbs the impulse generated by the water entry, reducing the water entry load. The limiting and disengaging mechanism limits the overall device and separates it from the vehicle. Traditional vehicles are cylindrical with a long cylindrical section, which is connected to the fairing by expansion bolts. However, the front end structure of a supercavitating vehicle is more complex. Its front end does not have a cylindrical section like that of a conventional vehicle, but rather a frustum section that gradually increases in size. If holes are made in the smaller frustum section, it will affect its structural strength. Furthermore, the fairing and the frustum section of the vehicle are in line contact. Therefore, when the vehicle moves in the air, the connection between the buffer head cap and the vehicle will be unstable. Aerodynamic loads will cause the buffer head cap to vibrate radially along the vehicle, resulting in a deviation in the attitude and position of the head cap during water entry impact, thus affecting the load reduction effect.
[0005] Therefore, there is a need to provide a high-speed water entry buffer cap for supercavitating vehicles to solve the above problems. Summary of the Invention
[0006] This invention provides a high-speed water entry buffer cap for supercavitating vehicles. By setting a positioning component to position the fairing, it solves the problem that existing aerodynamic loads cause the buffer cap to vibrate radially along the vehicle body, resulting in deviations in the cap's attitude and position during water entry impact, thus affecting the load reduction effect.
[0007] The present invention provides a high-speed water entry buffer cap for a supercavitating vehicle, comprising the following technical solution:
[0008] fairing;
[0009] An energy-absorbing component includes multiple foam plastic bodies with different densities, and the multiple foam plastic bodies are arranged sequentially inside the flow guide shroud along the flow direction of the flow guide shroud.
[0010] And a positioning component, which is located inside the fairing, with its positioning end positioned between the two fairing bowls of the hull.
[0011] Preferably, the density of the foam plastic body increases sequentially along the flow direction of the flow guide.
[0012] Preferably, the foam body is made of polymethacrylimide, rigid polyurethane foam, or aluminum foam.
[0013] Preferably, the fairing includes a pointed arched cap and a cylinder, with the open end of the pointed arched cap connected to one end of the cylinder.
[0014] Preferably, one foam plastic body and the pointed arch body have the same internal shape and are disposed inside the pointed arch body, while the other foam plastic body is disposed near the section where the cylinder connects to the pointed arch body.
[0015] Preferably, the positioning component includes multiple arc-shaped plates, which form a tube. The tube is connected to the cylinder by a connector. Each arc-shaped plate has a limiting plate on its inner arc surface. The limiting plate is positioned between two flow guide bowls of the vehicle. One end of the arc-shaped plate contacts the foam plastic body inside the cylinder, and the other end of the arc-shaped plate is provided with a connecting plate. Multiple connecting plates form an installation hole for connecting to the head of the vehicle.
[0016] Preferably, the connector includes a positioning screw that passes through the cylinder to connect the cylinder and the arc plate.
[0017] Preferably, the connectors and positioning components are made of nylon or polytetrafluoroethylene.
[0018] Preferably, the fairing is made of 8200 resin material.
[0019] Preferably, every two adjacent foam plastic bodies are connected, and the outer peripheral surface of the foam plastic body is connected to the inner wall of the flow guide.
[0020] The beneficial effects of this invention are:
[0021] 1. By setting a positioning component, the positioning end of the positioning component is placed between the two flow guide bowls to achieve connection and positioning between the flow guide and the aircraft body. This allows the positioning component to limit the relative position of the buffer cap on the aircraft body during navigation, while preventing the buffer cap from moving on the aircraft body. This avoids the vibration of the buffer cap along the radial direction of the aircraft body caused by aerodynamic loads when the aircraft body is moving in the air, and reduces the probability of the buffer cap's attitude position deviating when the aircraft body enters the water. At the same time, the combination of foam plastic bodies of different densities can buffer the impact force, thereby ensuring the load reduction effect.
[0022] 2. This invention uses foam plastic bodies with progressively increasing density along the flow direction of the guide shroud. When the water flow impact energy shatters the guide shroud, it first acts on the first foam plastic body, which absorbs the water flow impact energy for the first time. Then, the second foam plastic body absorbs it for the second time, and so on until the last foam plastic body has absorbed the water flow impact energy. During the energy absorption process, since the impact energy propagates at different speeds in media of the same material but different densities, as the density of the foam plastic bodies increases sequentially, the foam plastic bodies in the entire energy absorption assembly form a stepped absorption of the impact force. As the impact energy is continuously absorbed, the impact force continuously decreases, and the density of the foam plastic bodies increases, resulting in better energy absorption. Therefore, better absorption of water flow impact energy is achieved, thereby ensuring the safety of the linkage structure of the supercavitating vehicle. Attached Figure Description
[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0024] Figure 1 This is a schematic diagram of the overall structure of an embodiment of a high-speed water entry buffer cap for a supercavitating vehicle according to the present invention;
[0025] Figure 2 This is a schematic diagram showing the connection between the high-speed water entry buffer cap of a supercavitating vehicle and the vehicle body according to the present invention.
[0026] Figure 3 A schematic diagram of the structure of a supercavitating vehicle;
[0027] Figure 4 This is a schematic diagram of the fairing structure;
[0028] Figure 5 This is a structural diagram of the positioning component;
[0029] In the diagram: 1. Buffer cap; 2. Aircraft body; 3. Linkage structure; 4. Flow guide bowl; 5. Flow guide cover; 6. Foam plastic body; 7. Arc plate; 8. Connector; 51. First threaded hole; 71. Limiting plate; 72. Second threaded hole. Detailed Implementation
[0030] 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.
[0031] An embodiment of the high-speed water entry buffer cap for a supercavitating vehicle according to the present invention, such as... Figure 2 As shown, the buffer cap 1 is connected to the hull 2, specifically, as... Figure 1 As shown, the buffer cap 1 includes: a flow guide 5, an energy absorption component, and a positioning component; wherein, the energy absorption component includes multiple foam plastic bodies 6, the multiple foam plastic bodies 6 are made of the same material but have different densities, and the multiple foam plastic bodies 6 are arranged sequentially inside the flow guide 5 along the flow direction of the flow guide 5; the positioning component is arranged inside the flow guide 5 on the side opposite to the energy absorption component, and the positioning end of the positioning component is arranged between the two flow guide bowls 4 of the vehicle body 2 to prevent the flow guide 5 from moving.
[0032] Specifically, to better absorb the impact energy of the water flow after the supercavitating vehicle enters the water at high speed, the density of the foam plastic body 6 increases sequentially along the flow direction of the guide shield 5. That is, when the impact energy of the water flow breaks the guide shield 5, it will first act on the first foam plastic body 6, which absorbs the impact energy for the first time. Then, the second foam plastic body 6 absorbs it for the second time, and so on until the last foam plastic body 6 completes the absorption of the impact energy. During the energy absorption process, since the impact energy propagates at different speeds in media of the same material but different densities, as the density of the foam plastic body 6 increases sequentially, the foam plastic bodies 6 in the entire energy absorption component form a stepped absorption of the impact force. As the impact energy is continuously absorbed, the impact force continuously decreases, and the density of the foam plastic body 6 increases, resulting in better energy absorption. Therefore, better absorption of the impact energy of the water flow is achieved, thereby ensuring the safety of the linkage structure of the supercavitating vehicle.
[0033] Specifically, the foam body 6 is made of polymethacrylimide, rigid polyurethane foam, or aluminum foam. In this embodiment, polymethacrylimide of different densities is used to compose the foam body 6. Polymethacrylimide is the foam material with the highest strength and stiffness at the same density, and has a strong ability to absorb impact energy. In addition, polymethacrylimide, rigid polyurethane foam, or aluminum foam are all lightweight porous energy-absorbing materials.
[0034] It should be noted that for porous energy-absorbing materials, the higher the density, the finer the internal pore structure, and therefore the higher the strength and stiffness of the material. When subjected to the compression of water and the vehicle, it is less likely to fail and break, thus exhibiting a better buffering effect. Since the initial impact is the strongest, a low-density material is selected, with large and numerous internal pores, providing a large buffering space. As subsequent impacts weaken, a high-density material is selected, with smaller internal pore spaces, making the material more compact overall, thus achieving a longer buffering effect.
[0035] Specifically, the fairing 5 includes a pointed arched cap and a cylinder, with the open end of the pointed arched cap connected to one end of the cylinder.
[0036] Specifically, one foam plastic body 6 has the same internal shape as the pointed arch cap body and is disposed inside the pointed arch cap body, while another foam plastic body 6 is disposed in the section near the connection between the cylinder and the pointed arch cap body.
[0037] Specifically, due to the specific structure of the aircraft's shape, traditional aircraft are cylindrical with a relatively long cylindrical section, while supercavitary aircraft have a gradually changing structure, smaller at the front and larger at the rear. Without a positioning component, the tail end of the fairing would be in line contact with the aircraft, leading to an unstable connection between the entire buffer cap and the aircraft. In this embodiment, the positioning component includes multiple arc-shaped plates 7, which form a tube. The tube is connected to the cylinder via a connector. Each arc-shaped plate 7 has a limiting plate 71 on its inner arc surface. The limiting plate 71 is configured to... Between the two guide bowls 4 of the navigator 2, both sides of the limiting plate 71 are in contact with the corresponding guide bowl 4. The limiting plate 71 is used to restrict the movement of the tube formed by the arc plate in the length direction of the navigator 2. One end of the arc plate 7 is in contact with the foam plastic body 6 inside the cylinder, and the other end of the arc plate 7 is provided with a connecting plate. Multiple connecting plates form a mounting hole for connecting with the head of the navigator 2. The connecting component includes a positioning screw 8 and corresponding threaded holes opened on the cylinder and the tube. The positioning screw 8 connects the cylinder and the tube through the threaded holes. Specifically, as shown in the figure... Figure 1 and Figure 4 and Figure 5As shown, after the positioning screw 8 passes through the first threaded hole 51 on the fairing 5, it is connected to the second threaded hole 72 on the arc plate 7 of the positioning assembly, thus realizing the connection between the fairing 5 and the arc plate 7 of the positioning assembly, as well as the positioning of the fairing 5 by the positioning assembly. During installation, the arc plate 7 is first placed on the outer circumference of the aircraft body, then multiple arc plates 7 are assembled into a tube, and then the tube is fitted into the cylinder of the fairing 5. Finally, the fairing 5 and the arc plate 7 of the positioning assembly are connected by the positioning screw 8.
[0038] Specifically, the connectors and positioning components are made of nylon or polytetrafluoroethylene.
[0039] Specifically, in order to ensure the surface quality and toughness of the flow guide 5, to ensure the integrity of the overall structure of the buffer cap before entering the water, and to ensure that the pointed arch cap of the flow guide 5 can break smoothly when it collides with the water surface, the flow guide 5 in this embodiment is made of 8200 resin material.
[0040] Specifically, in order to prevent the foam fragments 6 from detaching after the pointed arch of the flow guide 5 breaks, in this embodiment, every two adjacent foam plastic bodies 6 are bonded together, and the outer peripheral surface of the foam plastic body 6 is bonded to the inner wall of the flow guide 5.
[0041] Specific working principle
[0042] In use, the supercavitating vehicle is launched using a rocket-assisted method. The buffer cap is installed at the front of the vehicle's head. When the trajectory changes from an air ballistic trajectory to an underwater ballistic trajectory, the shield 5 of the buffer cap first has a violent impact with the water surface. The pointed arch of the shield 5 breaks, exposing the energy-absorbing components inside, which are then compressed by the water medium. After being compressed, the energy-absorbing components are isolated from the direct action of the water medium on the linkage structure of the supercavitating vehicle due to the deformation and energy-absorbing characteristics of the foam plastic body 6, thus reducing the impact load upon entering the water. As the entry process progresses, the foam plastic body 6 is continuously compressed and ruptures. At the same time, the rear end of the buffer cap is continuously expanded by the vehicle until it ruptures. When the entry depth reaches a certain level, the water buffer cap separates from the vehicle, without affecting the hydrodynamic shape of the supercavitating vehicle during normal navigation.
[0043] In summary, the high-speed water entry buffer cap for a supercavitating vehicle provided by this invention, by setting a positioning component with its positioning end between two flow guide bowls, achieves connection and positioning between the flow guide and the vehicle. This allows the positioning component to restrict the relative position of the buffer cap on the vehicle during navigation, preventing movement of the buffer cap on the vehicle. This avoids aerodynamic loads causing radial vibration of the buffer cap along the vehicle during airborne motion, reducing the probability of attitude position deviation of the buffer cap during water entry impact. Furthermore, the combination of foam plastic bodies of varying densities buffers the impact force, ensuring a load reduction effect. By setting foam plastic bodies with progressively increasing density along the flow guide direction of the flow guide, the impact energy of the water flow is reduced. After the deflector is shattered, the impact energy is first absorbed by the first foam plastic body. The first foam plastic body absorbs the impact energy of the water flow for the first time. Then, the second foam plastic body absorbs it for the second time, and so on until the last foam plastic body has absorbed the impact energy of the water flow. During the energy absorption process, since the impact energy propagates at different speeds in media of the same material but different densities, as the density of the foam plastic bodies increases sequentially, the foam plastic bodies in the entire energy absorption component form a stepped absorption of the impact force. As the impact energy is continuously absorbed, the impact force continuously decreases, and the density of the foam plastic bodies increases, the energy absorption effect becomes better. Therefore, better absorption of the impact energy of the water flow is achieved, thereby ensuring the safety of the linkage structure of the supercavitating vehicle.
[0044] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A high-speed water entry buffer cap for a supercavitating vehicle, characterized in that, include: A fairing, comprising a pointed arched cap and a cylinder, wherein the open end of the pointed arched cap is connected to one end of the cylinder; An energy-absorbing component includes multiple foam plastic bodies with different densities, and the multiple foam plastic bodies are arranged sequentially inside the flow guide shroud along the flow direction of the flow guide shroud. The system also includes a positioning component, which is located inside the fairing. Its positioning end is positioned between the two fairing bowls of the aircraft to prevent the fairing from moving. The positioning component includes multiple arc-shaped plates that form a tube. The tube is connected to the cylinder via a connector. Each arc-shaped plate has a limiting plate on its inner arc surface. The limiting plate is positioned between the two fairing bowls of the aircraft. One end of the arc-shaped plate contacts the foam plastic body inside the cylinder. The other end of the arc-shaped plate has a connecting plate. The multiple connecting plates form a mounting hole for connecting to the head of the aircraft.
2. The high-speed water entry buffer cap for a supercavitating vehicle according to claim 1, characterized in that, The density of the foam plastic body increases sequentially along the flow direction of the flow guide shroud.
3. The high-speed water entry buffer cap for a supercavitating vehicle according to claim 1, characterized in that, The foam body is made of polymethacrylimide, rigid polyurethane foam, or aluminum foam.
4. The high-speed water entry buffer cap for a supercavitating vehicle according to claim 1, characterized in that, in, One foam plastic body has the same internal shape as the pointed arch cap body and is disposed inside the pointed arch cap body, while another foam plastic body is disposed near the section where the cylinder connects to the pointed arch cap body.
5. The high-speed water entry buffer cap for a supercavitating vehicle according to claim 1, characterized in that, The connector includes a positioning screw that passes through the cylinder to connect the cylinder and the arc plate.
6. The high-speed water entry buffer cap for a supercavitating vehicle according to claim 1, characterized in that, Both the connector and the positioning component are made of nylon or polytetrafluoroethylene.
7. The high-speed water entry buffer cap for a supercavitating vehicle according to claim 1, characterized in that, The air deflector is made of 8200 resin material.
8. The high-speed water entry buffer cap for a supercavitating vehicle according to claim 1, characterized in that, Each pair of adjacent foam plastic bodies is connected, and the outer peripheral surface of the foam plastic body is connected to the inner wall of the flow guide.