Reentry vehicle head repeatable effusion thermal protection device and control method thereof

Abstract

The embodiment of the present application provides a reentry vehicle head repeatable jet heat protection device and a control method thereof. The heat protection device comprises: a load cabin, a gas collecting bottle and a first electromagnetic valve in communication with the gas collecting bottle are arranged in the load cabin; and a protection assembly, the protection assembly comprises a heat protection member arranged at the head of the load cabin, the heat protection member is provided with a gas inlet and outlet, and the gas inlet and outlet are in communication with the first electromagnetic valve, wherein, when the gas pressure in the gas collecting bottle is greater than the external gas pressure, the gas collecting bottle is used for absorbing the external gas from the gas inlet and outlet to store the gas, and when the gas pressure in the gas collecting bottle is less than the external gas pressure, the gas collecting bottle is used for spraying the stored gas out of the gas inlet and outlet. The embodiment of the present application uses the collected gas as a release jet working medium to protect the head of the vehicle from heat, and the process of collecting and releasing the gas can be repeatedly used, can be suitable for various ballistic modes, and is more mobile.

Description

Technical Field

[0001] This application relates to the field of aircraft technology, and more specifically, to a reusable jet device for the thermal protection head of a reentry vehicle and its control method. Background Technology

[0002] With the development of the space industry, space transportation and deep space exploration missions will be the focus of future research. Compared with traditional reentry deceleration methods and inflatable reentry vehicles, mechanically deployable reentry vehicles have received widespread attention both domestically and internationally in recent years due to their advantages such as small envelope constraint, high payload efficiency, and good deceleration effect. During the reentry process, the reentry vehicle successively passes through rarefied flow, transitional flow, and continuous flow regions. A large amount of aerodynamic heat is generated during high-speed flight, causing ablation of the vehicle surface and the overall structure. Therefore, how to effectively and reasonably protect the reentry vehicle from thermal damage is one of the urgent problems to be solved.

[0003] In recent years, many scholars at home and abroad have proposed various methods for drag reduction and heat protection, such as: reverse jetting, adding drag-reducing rods, adding aerodynamic disks, windward concave cavities, energy deposition, and many combinations thereof. For example, in related technologies, liquid is placed at the front end of the aircraft's nose and a support rod is installed to change the flow field structure while simultaneously causing the liquid to evaporate through frictional heat and then jetting.

[0004] Existing methods of thermal protection have many problems. If jet heat protection is used, the working fluid will occupy a large space inside the aircraft. If additional devices are installed, the exposed outer end of the aircraft will suffer severe ablation and will affect the shape and center of gravity of the reentry vehicle, and it cannot be reused. Summary of the Invention

[0005] The purpose of this application is to provide a reusable jet thermal protection device for the head of a reentry vehicle and its control method, so as to solve the problem that the thermal protection of reentry vehicle thermal protection devices in the prior art is poor and cannot be reused.

[0006] This application provides a reusable jet thermal protection device for the nose of a reentry vehicle, comprising: a payload compartment, wherein a gas collecting bottle and a first solenoid valve connected to the gas collecting bottle are disposed within the payload compartment; and a protective assembly, wherein the protective assembly includes a heat shield disposed at the nose of the payload compartment, the heat shield having a gas inlet and outlet connected to the first solenoid valve, wherein when the gas pressure inside the gas collecting bottle is lower than the external gas pressure, the gas collecting bottle is used to absorb external gas from the gas inlet and outlet for storage, and when the gas pressure inside the gas collecting bottle is higher than the external gas pressure, the gas collecting bottle is used to eject the stored gas through the gas inlet and outlet.

[0007] The reusable jet thermal protection device for the reentry vehicle nose of this application embodiment does not require carrying excess gaseous working fluid internally. Instead, it collects external gas during operation as the jet working fluid and uses the collected gas as the released jet working fluid to provide thermal protection for the vehicle nose. Furthermore, this gas collection and release process is reusable. In addition, the thermal protection device has a simplified structure and reduced added mass, making it easier to carry a larger payload. Compared with drag reduction methods such as drag-reducing rods and pneumatic discs, the method of controlling the collection and release of the jet mass via a solenoid valve for thermal protection is more stable and controllable. It eliminates the need to consider ablation and changes to the vehicle's shape and center of gravity, resulting in higher safety and better thermal protection. Moreover, the start and stop of the jet are controlled by opening and closing the solenoid valve, allowing for reasonable control based on the vehicle's environment. It is applicable to various ballistic patterns and offers greater maneuverability.

[0008] In some embodiments, the heat shield has a tapered protective surface.

[0009] In this embodiment, the conical heat shield plays a good role in deceleration and heat insulation during the flight of the aircraft.

[0010] In some embodiments, the gas inlet and outlet are located on the axis of the payload compartment.

[0011] In this embodiment, the gas inlet and outlet located on the axis of the payload compartment allow for faster gas collection and, when releasing gas, are more effective in pushing the shock wave from the nose of the aircraft away from the surface, thereby reducing the impact of aerodynamic heating of the nose of the aircraft.

[0012] In some embodiments, one end of the first solenoid valve is connected to the gas collecting bottle, and the other end is connected to the heat-resistant component.

[0013] In this embodiment, the heat-resistant component serves as a heat-resistant cone, and threads can be provided at the ends of the gas inlet and outlet to facilitate threaded connection and sealing with the first solenoid valve. The first solenoid valve can be a DN4 direct-acting solenoid valve, which controls the opening and closing of the circuit via signal control. Its two ends are connected to the ends of the gas inlet and outlet and the gas collecting bottle, respectively, and the first solenoid valve can be opened and closed multiple times.

[0014] In some embodiments, the protective assembly further includes protective wings surrounding the outer periphery of the payload compartment. The protective wings have a retracted state (folded to the outer periphery of the payload compartment) and an extended state (extended outward relative to the outer periphery of the payload compartment). The protective wings include multiple deployable rods, each deployable rod including a rod body and a jetting device disposed within the rod body. The front end of the rod body is movably connected to the payload compartment, and the rear end of the rod body is provided with a jetting hole. The side wall of the rod body is provided with an deployment hole, and the jetting hole and the deployment hole are respectively connected to the jetting device. When the jetting gas ejected by the jetting device is ejected from the deployment hole, the deployable rod, under the reaction force of the jetting gas, causes the protective wings to switch from the retracted state to the extended state. When the jetting gas ejected by the jetting device is ejected from the jetting hole, the jetting gas provides thermal protection to the rear end of the deployable rod.

[0015] This embodiment utilizes a jet of medium carried within the internal space of the deployment rod for both aircraft deployment and overall thermal protection. This improves space utilization without affecting the original payload capacity of the aircraft. Furthermore, deployment is achieved through the jet, reducing the need for some motor mechanisms. Compared to traditional drag reduction methods such as drag-reducing rods and pneumatic discs, this thermal protection method is more stable and controllable, eliminates concerns about ablation and alterations to the aircraft's shape and center of gravity, is reusable, offers high safety, and provides superior thermal protection.

[0016] In some embodiments, the jet device includes: a gas storage cylinder, a second solenoid valve, and a gas collection chamber arranged sequentially from the front end to the rear end of the rod, wherein the second solenoid valve is connected between the gas storage cylinder and the gas collection chamber, and the gas collection chamber is connected to the jet hole and the expansion hole.

[0017] In this embodiment, the gas storage cylinder and the gas collection chamber are connected by a second solenoid valve. The opening and closing of the second solenoid valve starts and stops the jet, which facilitates reasonable and precise control according to the environment in which the aircraft is located.

[0018] In some embodiments, the gas collection chamber includes a connected cavity, a plurality of axial jet channels and a lateral jet channel, and a plurality of jet holes are provided, each of the plurality of jet holes being connected to a plurality of axial jet channels in a one-to-one correspondence, and the expansion hole being connected to the lateral jet channel.

[0019] In this embodiment, the axial jet channel is multi-channel and the lateral jet channel is single-channel, so that the jet medium in the gas storage cylinder is reasonably distributed, allowing more jets to be ejected through the jet holes, thereby providing better thermal protection for the aircraft.

[0020] In some embodiments, it further includes: a deployment mechanism, the deployment mechanism including a connecting rod and a slider; The front end of the rod is hinged to the load chamber, and a slide rail is provided on the rod. One end of the connecting rod is hinged to the load chamber, and the other end is connected to the slider. The slider is slidably connected to the slide rail.

[0021] In this embodiment, when the unfolding rod is subjected to the reaction force of the gas injected from the unfolding hole, the unfolding operation of each unfolding rod is realized through the cooperation of the connecting rod, the slider and the slide rail, and the unfolding process is more stable.

[0022] In some embodiments, the method further includes: connecting a skin to each of the deploying rods, the skin including a pneumatic deceleration surface connecting the front end to the rear end of each of the deploying rods and connected to the heat shield.

[0023] In this embodiment, the aerodynamic deceleration surface and the heat shield provide thermal insulation and protection for the entire aircraft.

[0024] This application also provides a control method for a reusable jet thermal protection device for the nose of a reentry vehicle, applied to the thermal protection device described in any of the above embodiments. The method includes: extracting gas from the gas collecting bottle to make the pressure of the gas collecting bottle lower than the external air pressure, and closing a first solenoid valve; determining the position of the vehicle during its ascent aboard a launch vehicle, and when the vehicle is at a first position, opening the first solenoid valve to allow the gas collecting bottle to collect external gas from the gas inlet and outlet, and closing the first solenoid valve to store the collected gas in the gas collecting bottle; determining the reentry mode of the vehicle when performing a reentry and return mission, and controlling the first solenoid valve to open once or multiple times according to the reentry mode, so that the gas collecting bottle ejects the stored gas through the gas inlet and outlet once or multiple times.

[0025] In this embodiment, the method of controlling the jet mass collection and release for thermal protection via an electromagnetic valve is more stable and controllable. It eliminates the need to consider ablation and changes to the aircraft's shape and center of gravity, resulting in high safety and superior thermal protection. Furthermore, controlling the jet's start and stop via the electromagnetic valve allows for appropriate control based on the aircraft's environment, making it applicable to various ballistic patterns and enhancing maneuverability. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 A schematic diagram of the deployed state of a reusable jet thermal protection device for the nose of a reentry vehicle provided in this application embodiment; Figure 2 A schematic diagram of the retracted state of a reusable jet thermal protection device for the nose of a reentry vehicle provided in this application embodiment; Figure 3 A schematic diagram of the protective wing structure of a reusable jet thermal protection device for the nose of a reentry vehicle provided in this application embodiment; Figure 4 Another perspective schematic diagram of a reusable jet thermal protection device for the nose of a reentry vehicle provided in an embodiment of this application; Figure 5 A schematic diagram of the deployment rod of a reusable jet thermal protection device for the nose of a reentry vehicle provided in this application embodiment; Figure 6 A schematic diagram of the deployed and retracted states of a reusable jet thermal protection device for the nose of a reentry vehicle, provided as an embodiment of this application; Figure 7 A schematic diagram of the deployment rod structure of a reusable jet thermal protection device for the nose of a reentry vehicle provided in an embodiment of this application; Figure 8 A schematic diagram of the deployment rod structure of a reusable jet thermal protection device for the nose of a reentry vehicle, provided for another embodiment of this application; Figure 9 A schematic diagram of a reusable jet thermal protection device for the nose of a reentry vehicle without protective wings, provided in this application embodiment; Figure 10 A flowchart of a jet thermal protection method for a reusable jet thermal protection device for the nose of a reentry vehicle, provided in this application embodiment; Figure 11 This is a schematic diagram of a ballistic reentry trajectory for a reentry vehicle provided in an embodiment of this application; Figure 12 A schematic diagram of a skip reentry trajectory for a reentry vehicle provided in an embodiment of this application; Figure 13 This is a schematic diagram of the working process of a reentry vehicle during ballistic reentry, provided in an embodiment of this application. Figure 14 This is a schematic diagram of the working process of a reentry vehicle during a skip reentry, provided in an embodiment of this application. Icons: 10-Payment compartment; 11-Gas collection bottle; 12-First solenoid valve; 13-Gas inlet / outlet; 20-Protective wing; 21-Deployment rod; 22-Gas storage bottle; 23-Second solenoid valve; 24-Gas collection chamber; 201-Front end; 202-Tail end (shoulder); 203-Jet hole; 204-Deployment hole; 25-Skin; 251-Heat shield; 252-Pneumatic deceleration surface. Detailed Implementation

[0028] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0029] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0030] Please refer to Figure 9 , Figure 9 This is a schematic diagram of a reusable jet thermal protection device for the nose of a reentry vehicle without its protective wing, provided as an embodiment of this application.

[0031] This application provides a reusable jet thermal protection device for the nose of a reentry vehicle, including: a payload compartment 10 and protective components.

[0032] The load chamber 10 provides space for the load and may be cylindrical. A gas collecting bottle 11 and a first solenoid valve 12 connected to the gas collecting bottle 11 are disposed within the load chamber 10. The gas collecting bottle 11 is used to collect external gas by opening via the first solenoid valve 12 and to store external gas by closing via the first solenoid valve 12. Furthermore, the gas collecting bottle 11 is also used to eject the stored gas to form a jet by opening via the first solenoid valve 12.

[0033] The protective assembly provides thermal protection for the aircraft during flight. The assembly may include a heat shield 251 located at the head of the payload bay 10. The heat shield 251 has a gas inlet / outlet 13 connected to a first solenoid valve 12. The heat shield 251 may be generally conical, with a conical surface that provides effective deceleration and heat insulation during flight. Specifically, when the pressure inside the gas collection bottle 11 is lower than the external pressure, the gas collection bottle 11 absorbs and stores external gas from the gas inlet / outlet 13; and when the pressure inside the gas collection bottle 11 is higher than the external pressure, the gas collection bottle 11 discharges the stored gas through the gas inlet / outlet 13, thereby providing thermal protection for the aircraft's nose.

[0034] Before the spacecraft takes off, the gas in the gas collection cylinder 11 built into the payload compartment 10 can be evacuated to a lower pressure (e.g., less than 1000 Pa) to ensure that its pressure is lower than the external air pressure during low-altitude ascent, and the solenoid valve is in the closed state. During the ascent of the reentry vehicle carrying the launch vehicle, at low altitude (e.g., 10km-20km), the first solenoid valve 12 can be opened to connect the built-in gas collection cylinder 11 with the outside. At this time, since the external atmospheric pressure is much greater than the pressure inside the gas collection cylinder 11, the external gas enters the gas collection cylinder 11 through the gas inlet / outlet 13 and the first solenoid valve 12, filling the gas collection cylinder 11. The pressure inside the gas collection cylinder 11 gradually increases. When the pressure inside the cylinder reaches a set value (e.g., 5000 Pa) or the internal and external air pressures are balanced and filling stops, the first solenoid valve 12 is closed, sealing the passage between the gas collection cylinder 11 and the outside atmosphere, and the jet working fluid (collected gas) is stored in the cylinder. When a reentry vehicle performs a return mission at high altitude, it can be divided into two types: ballistic reentry and semi-ballistic skip reentry, as detailed below: In one example, if it is a ballistic reentry, the reentry vehicle returns at high speed. Through ballistic calculations, it can be known that the maximum heat flux density on the surface of the vehicle during the return process generally occurs at some point between 40-60 km. Therefore, when the flight condition is, for example, at about 60 km, the first solenoid valve 12 can be opened. At this time, since the pressure of the gas collecting bottle 11 inside the payload compartment 10 is greater than the external atmospheric pressure, the jet working medium (the gas collected in the gas collecting bottle 11) is ejected from the gas inlet and outlet 13 through the first solenoid valve 12, pushing the shock wave at the head of the vehicle away from the surface, reducing the load on the surface of the vehicle, and playing a role in providing thermal protection for the stagnation point.

[0035] In another example, if it is a semi-ballistic skip reentry, the first solenoid valve 12 is rapidly opened to inject a jet as the flight altitude decreases, providing initial thermal protection to the aircraft surface. For example, when pressure equilibrium is reached around 80km, the first solenoid valve 12 is closed, keeping the gas collection cylinder 11 at low pressure. As the aircraft approaches the heat flux peak and begins to rise again, the first solenoid valve 12 is opened, again relying on external pressure greater than the cylinder pressure to collect external gas to obtain the jet working medium. During the second reentry, when the heat flux peak is reached, the jet is injected again. At this point, the aircraft speed decreases, and the jet provides better thermal protection.

[0036] When the flight altitude is below 40km or the internal gas pressure is equal to the external pressure, the first solenoid valve is closed and the jet stops.

[0037] The reusable jet thermal protection device for the reentry vehicle nose of this application embodiment does not require carrying excess gaseous working fluid internally. Instead, it collects external gas during operation as the jet working fluid and uses the collected gas as the released jet working fluid to provide thermal protection for the vehicle nose. Furthermore, this gas collection and release process is reusable. This thermal protection device has a simplified structure and reduced added mass, facilitating the carrying of larger payloads. Compared with drag reduction methods such as drag-reducing rods and aerodynamic discs, its thermal protection method is more stable and controllable, eliminating concerns about ablation and alterations to the vehicle's shape and center of gravity. It is reusable, offers high safety, and provides superior thermal protection. The start and stop of the jet are controlled by the on / off switching of a first solenoid valve, allowing for appropriate control based on the vehicle's environment. It is applicable to various ballistic patterns and offers greater maneuverability.

[0038] In some embodiments, the gas inlet / outlet 13 may be located on the axis of the payload compartment 10. During flight, gas collection is faster and gas release is more conducive to pushing the shock wave of the aircraft head away from the surface of the object to reduce the impact of aerodynamic heating of the aircraft head.

[0039] In some embodiments, one end of the first solenoid valve 12 is connected to the gas collecting bottle 11, and the other end is connected to the heat shield 151. For example, the heat shield 151 serves as a heat shield cone, and threads can be provided at the ends of the gas inlet / outlet 13 to facilitate threaded connection and sealing with the first solenoid valve 12. The first solenoid valve 12 can be a DN4 direct-acting solenoid valve, which controls the opening and closing of the circuit via signal control. Its two ends are connected to the ends of the gas inlet / outlet 13 and the gas collecting bottle 11, respectively, and the first solenoid valve 12 can be opened and closed multiple times.

[0040] In some embodiments, please refer to Figure 1 , Figure 2 and Figure 7 , Figure 1 A schematic diagram of the deployed state of a reusable jet thermal protection device for the nose of a reentry vehicle provided in this application embodiment; Figure 2 A schematic diagram of the retracted state of a reusable jet thermal protection device for the nose of a reentry vehicle provided in this application embodiment; Figure 7 This is a schematic diagram of the deployed structure of a reusable jet thermal protection device for the nose of a reentry vehicle, provided in one embodiment of this application.

[0041] In the thermal protection device of this application embodiment, the protective component further includes protective wings 20. The protective wings 20 are disposed around the outer periphery of the load chamber 10, and the protective wings 20 have a retracted state where they are folded into the outer peripheral wall of the load chamber 10. Figure 2 (as shown) and the deployed state with the outer peripheral wall of the relative load compartment 10 extended outwards (as shown) Figure 1(As shown). The protective wing 20 can be retracted or deployed. During the launch and on-orbit operation of the spacecraft, the protective wing 20 is in the retracted state, and during the reentry process, the protective wing 20 is in the deployed state. In the retracted state, the protective wing 20 and the payload compartment 10 are roughly cylindrical in shape. In the deployed state, the protective wing 20 and the payload compartment 10 are separated and roughly umbrella-shaped.

[0042] In one embodiment, reference is made to Figure 7 The protective wing 20 includes multiple deployable rods 21, each with a hollow structure. These rods are arranged around the load chamber 10, with the front end of each rod 21 movably connected to the load chamber 10. Each rod 21 is deployed via a power unit or gas within the load chamber 10, allowing the protective wing 20 to switch from a retracted to an deployed state. For example, the load chamber 10 is internally connected to the hollow deployable rods 21, and the sidewalls of the hollow deployable rods 21 have lateral deployment holes 204. When the protective wing 20 needs to be deployed, high-pressure gas is supplied to the hollow deployable rods 21 through the load chamber 10. The high-pressure gas is then ejected from the lateral deployment holes 204 on the sidewalls of the hollow deployable rods 21, providing the necessary power for the deployment of the rods 21.

[0043] In another embodiment, the protective wing 20 can be deployed via a separate jet device and provide jet thermal protection at the shoulder. See details. Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 8 , Figure 3 A schematic diagram of the protective wing structure of a reusable jet thermal protection device for the nose of a reentry vehicle provided in this application embodiment; Figure 4 This is another schematic diagram of a reusable jet thermal protection device for the nose of a reentry vehicle, provided as an embodiment of this application. Figure 5 A schematic diagram of the deployment rod of a reusable jet thermal protection device for the nose of a reentry vehicle provided in this application embodiment; Figure 6 This is a schematic diagram showing the retracted state of the deployable jet thermal protection device for the nose of a reentry vehicle, provided as an embodiment of this application. For ease of explanation, [the diagram is omitted here]. Figure 5 and Figure 6 The protective wing in the middle only retains one deployment rod.

[0044] The protective wing 20 includes multiple deployable rods 21, each deployable rod 21 including a rod body and a jetting device disposed within the rod body, the front end 201 of the rod body (see...) Figure 5 The rod is movably connected to the load chamber 10, and the tail end 202 (see...) Figure 5 The rod is provided with a jet hole 203, and the side wall of the rod is provided with an expansion hole 204 (see...). Figure 8The jet orifice 203 and the expansion orifice 204 are respectively connected to the jet device inside the rod body. Understandably, multiple expansion rods 21 can be evenly arranged around the outer periphery of the payload compartment 10. The structure of each expansion rod 21 can be the same, and the front end is movably connected to the outer peripheral wall of the payload compartment 10, while the rear end 202 is a free end. The rear end 202 of the multiple expansion rods 21 forms the shoulder of the aircraft. The inventors found that for the aircraft, under certain flight conditions, due to the generation of shock waves and flow separation in the shoulder of the aircraft, the most severe thermal environment of the entire aircraft comes from the shoulder of the aircraft.

[0045] When the jet gas ejected from the jet device exits through the deployment hole 204, the protective wings 20 of each deployment rod 21 switch from a retracted state to an deployed state under the reaction force of the jet gas. When the jet gas ejected from the jet device exits through the jet hole 203, the jet gas provides thermal protection to the tail end 202 of the deployment rod 21. Optionally, the deployment rod 21 can be a hollow rod, with the deployment hole 204 located on the side wall of the deployment rod 21 near the load chamber 10. The hollow rod facilitates internal storage of the gas medium while reducing the overall weight. The deployment hole 204 is located on the side wall of the deployment rod 21 near the load chamber 10 to maximize the reaction force of the gas ejected from the deployment hole 204 on the deployment rod 21, facilitating the deployment of each deployment rod 21.

[0046] The reentry vehicle thermal protection device of this embodiment utilizes a jetting device inside the deployment rod 21 to eject jet gas during the reentry process. A portion of the jet gas exits from the deployment holes 204 on the side of the deployment rod 21. The reaction force of the jet gas on each deployment rod 21 causes the protective wings 20 to switch from a retracted state to an deployed state, forming an umbrella shape. The umbrella-shaped surface forms an aerodynamic deceleration surface 252, providing thermal insulation protection for the entire vehicle. Simultaneously, another portion of the jet gas exits from the jetting holes 203 at the tail end 202 of the deployment rod 21. This jet pushes the shock wave from the shoulder of the vehicle away from the surface, reducing the load on the shoulder surface and lowering its temperature, thus providing effective thermal protection for the shoulder of the vehicle (the tail end of the deployment rod 21). This reentry vehicle thermal protection device utilizes the internal space of the deployment rod 21 to carry a jetting medium for the deployment of the vehicle and for overall thermal protection, improving space utilization without affecting the original payload capacity. Furthermore, the jetting mechanism enables deployment, reducing the need for some motor components. Compared with traditional drag reduction methods such as drag reduction rods and aerodynamic discs, its thermal protection method is more stable and controllable, without the need to consider ablation or changes to the shape and center of gravity of the aircraft. It is reusable, has high safety, and better thermal protection effect.

[0047] In some embodiments, refer to Figure 8Each of the aforementioned deploying rods 21 contains a jetting device comprising: a gas storage cylinder 22, a second solenoid valve 23, and a gas collecting chamber 24 arranged sequentially from the front end 201 to the rear end 202 of the rod. The second solenoid valve 23 is connected between the gas storage cylinder 22 and the gas collecting chamber 24, and the gas collecting chamber 24 is connected to the jetting hole 203 and the deploying hole 204.

[0048] For example, the gas cylinder 22 can be a cylindrical cylinder that carries a jet of gas with a certain pressure. The gas medium can be nitrogen, oxygen, carbon dioxide, etc. The cylinder pressure and gas storage capacity can be designed and calculated based on flight conditions.

[0049] The second solenoid valve 23 can be a DN4 straight-through solenoid valve, which is threadedly connected to the gas cylinder 22. The main function of the solenoid valve is to control the circuit to disconnect. It can be a small solenoid valve with wireless or wired control. The solenoid valve is normally closed and opens when it receives a signal.

[0050] The gas collection chamber 24 may include a connected cavity, multiple axial jet channels, and lateral jet channels. Multiple jet holes 203 are provided, each corresponding to one of the multiple axial jet channels. The deployment hole 204 is connected to the lateral jet channels. As an example, the gas collection chamber 24 is threadedly connected to the second solenoid valve 23. The gas collection chamber may consist of a small circular cavity and jet channels. The jet channels are divided into axial and lateral groups. The lateral jet channels are single channels, primarily for facilitating the deployment of the reentry vehicle. The axial jet channels are a combination of multiple channels, providing thermal protection for the vehicle through the jet holes. By using multiple axial jet channels and single lateral jet channels, the jet medium within the gas storage cylinder 22 is rationally distributed, allowing more jet to be ejected through the jet holes 203, thus providing better thermal protection for the vehicle.

[0051] In some embodiments, see Figure 5 and Figure 6 The reentry vehicle thermal protection device also includes: a deployment mechanism, which includes a connecting rod 30 and a slider (not shown in the figure); the front end 201 of the rod is hinged to the payload compartment 10, and a slide rail (not shown in the figure) is provided on the rod; one end of the connecting rod 30 (lower end shown in the figure) is hinged to the payload compartment 10, and the other end (upper end shown in the figure) is connected to the slider, and the slider is slidably connected to the slide rail.

[0052] When the unfolding rod 21 is subjected to the reaction force of the gas ejected from the unfolding hole 204, the unfolding operation of each unfolding rod 21 is realized through the cooperation of the connecting rod 30, the slider and the slide rail, and the unfolding process is more stable.

[0053] Optionally, the load chamber 10 is provided with a first lifting lug 11 and a second lifting lug 12 arranged at intervals along the axial direction of the load chamber 10. The front end 201 of the rod is hinged to the load chamber 10 through the first lifting lug 11, and the connecting rod 30 is hinged to the load chamber 10 through the second lifting lug 12. The first lifting lug 11 and the second lifting lug 12 are respectively hinged to the unfolding rod 21 and the connecting rod, so as to avoid interference with the load chamber 10 during the unfolding process of each unfolding rod 21 and facilitate installation.

[0054] In some embodiments, refer to Figure 3 and Figure 4 The protective wing 20 also includes a skin 25 connected to each deployment rod 21. The skin is positioned in an umbrella shape over the head of the payload bay 10, and it retracts and expands along with the protective wing. The skin includes an aerodynamic deceleration surface 252 connecting the front and rear ends of each deployment rod 21 and connected to the heat shield 251. The aerodynamic deceleration surface 252 can connect with the conical surface formed by the protective component 251, thereby providing heat insulation protection for the entire aircraft.

[0055] This application also provides a control method for a reentry vehicle thermal protection device, applicable to the thermal protection device described in any of the above embodiments, with reference to... Figures 10-14 The method includes steps S11, S12, and S13.

[0056] In step S11, the gas in the gas collecting bottle is extracted so that the pressure in the gas collecting bottle is lower than the external air pressure, and the first solenoid valve is closed.

[0057] As mentioned above, before the aircraft takes flight, the gas in the gas collection bottle 11 built into the payload compartment 10 can be evacuated to a lower pressure (e.g., less than 1000 Pa) to ensure that its pressure is lower than the outside air pressure during low-altitude ascent, and the solenoid valve is in the closed state.

[0058] In step S12, the position of the spacecraft during the ascent of the launch vehicle is determined. When the spacecraft is in the first position, the first solenoid valve is opened to allow the gas collecting bottle to collect external gas from the gas inlet and outlet, and the first solenoid valve is closed to store the collected gas in the gas collecting bottle.

[0059] During the ascent of the reentry vehicle carried by the launch vehicle, the first position can be at a low altitude (e.g., 10km-20km). At this time, the first solenoid valve 12 can be opened, and the built-in gas collecting bottle 11 can be connected to the outside. At this time, since the external atmospheric pressure is much greater than the internal pressure of the gas collecting bottle 11, the external gas enters the gas collecting bottle 11 through the gas inlet and outlet 13 and the first solenoid valve 12 to fill the gas collecting bottle 11. The internal pressure of the gas collecting bottle 11 gradually increases. When the internal pressure of the gas bottle reaches the set value (e.g., 5000Pa) or the internal and external air pressures are balanced and filling stops, the first solenoid valve 12 is closed, sealing the channel between the gas collecting bottle 11 and the outside atmosphere. The jet working fluid (collected gas) is stored in the gas bottle.

[0060] In step S13, the reentry mode of the aircraft during the reentry and return mission is determined. Based on the reentry mode, the first solenoid valve is controlled to open once or multiple times, causing the gas collection bottle to eject the stored gas through the gas inlet and outlet once or multiple times. There are two possible reentry modes for the aircraft during the reentry and return mission: ballistic reentry and semi-ballistic skip reentry.

[0061] In one example, refer to Figure 11 and Figure 13 If it is a ballistic reentry, the reentry vehicle returns at high speed. Through ballistic calculations, it can be known that the maximum heat flux density on the surface of the vehicle during the return process generally occurs at some point between 40-60km. Therefore, when the flight condition is at, for example, about 60km, the first solenoid valve 12 can be opened. At this time, since the pressure of the gas collecting bottle 11 inside the payload compartment 10 is greater than the external atmospheric pressure, the jet working medium (the gas collected in the gas collecting bottle 11) is ejected from the gas inlet and outlet 13 through the first solenoid valve 12, pushing the shock wave at the head of the vehicle away from the surface, reducing the load on the surface of the vehicle, and playing a role in providing thermal protection for the stagnation point.

[0062] In another example, refer to Figure 12 and Figure 14 In the case of a semi-ballistic skip reentry, the first solenoid valve 12 is rapidly opened to inject a jet of gas as the flight altitude decreases, providing initial thermal protection to the aircraft surface. For example, when pressure equilibrium is reached around 80 km, the first solenoid valve 12 is closed, maintaining a low pressure in the gas collection cylinder 11. As the aircraft approaches the heat flux peak and begins to rise again, the first solenoid valve 12 is opened, again relying on external pressure exceeding the cylinder pressure to collect external gas and obtain the jet working medium. During the second reentry, when the heat flux peak is reached, the jet is injected again. At this point, the aircraft speed decreases, and the jet provides better thermal protection.

[0063] When the flight altitude is below 40km or the internal gas pressure is equal to the external pressure, the first solenoid valve is closed and the jet stops.

[0064] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can also be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram and / or flowchart, and combinations of blocks in block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0065] In addition, the functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0066] If the aforementioned functions are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0067] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application. It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0068] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0069] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. A reusable jet thermal protection device for the nose of a reentry vehicle, characterized in that, include: The load chamber contains a gas collecting bottle and a first solenoid valve connected to the gas collecting bottle. The protective assembly includes a heat shield disposed at the head of the payload compartment. The heat shield has a gas inlet and outlet, which are connected to the first solenoid valve. Wherein, when the gas pressure inside the gas collecting bottle is lower than the external gas pressure, the gas collecting bottle is used to absorb external gas from the gas inlet and outlet for storage, and when the gas pressure inside the gas collecting bottle is higher than the external gas pressure, the gas collecting bottle is used to spray the stored gas through the gas inlet and outlet. The protective assembly also includes protective wings, which are disposed around the outer periphery of the load chamber. The protective wings have a retracted state that is folded up against the outer periphery of the load chamber and an extended state that is extended outward relative to the outer periphery of the load chamber. The protective wing includes multiple deployable rods, each rod comprising a rod body and a jetting device disposed within the rod body. The front end of the rod body is movably connected to the load chamber, the rear end of the rod body is provided with a jetting hole, and the side wall of the rod body is provided with a deployable hole. The jetting hole and the deployable hole are respectively connected to the jetting device. When the jet gas ejected by the jet device is ejected from the deployment hole, the deployment rod, under the reaction force of the jet gas, causes the protective wing to switch from the retracted state to the deployed state; when the jet gas ejected by the jet device is ejected from the jet hole, the jet gas forms thermal protection for the tail end of the deployment rod.

2. The reusable jet thermal protection device for the nose of a reentry vehicle according to claim 1, characterized in that, The heat-resistant component has a conical protective surface.

3. The reusable jet thermal protection device for the nose of a reentry vehicle according to claim 1, characterized in that, The gas inlet and outlet are located on the axis of the load chamber.

4. The reusable jet thermal protection device for the nose of a reentry vehicle according to claim 3, characterized in that, One end of the first solenoid valve is threadedly connected to the gas collecting bottle, and the other end is threadedly connected to the gas inlet and outlet on the heat-resistant component.

5. The reusable jet thermal protection device for the nose of a reentry vehicle according to claim 1, characterized in that, The jet device includes: a gas storage cylinder, a second solenoid valve, and a gas collection chamber arranged sequentially from the front end to the rear end of the rod. The second solenoid valve is connected between the gas storage cylinder and the gas collection chamber, and the gas collection chamber is connected to the jet hole and the expansion hole.

6. The reusable jet thermal protection device for the nose of a reentry vehicle according to claim 5, characterized in that, The gas collection chamber includes interconnected cavities, multiple axial jet channels, and lateral jet channels. The jet holes are provided in multiple ways, and each jet hole is connected to a corresponding axial jet channel. The expansion hole is connected to the lateral jet channel.

7. The reusable jet thermal protection device for the nose of a reentry vehicle according to claim 1, characterized in that, Also includes: The unfolding mechanism includes a connecting rod and a slider; The front end of the rod is hinged to the load chamber, and a slide rail is provided on the rod. One end of the connecting rod is hinged to the load chamber, and the other end is connected to the slider. The slider is slidably connected to the slide rail.

8. The reusable jet thermal protection device for the nose of a reentry vehicle according to claim 1, characterized in that, Also includes: A skin is attached to each of the deployment rods, the skin including a pneumatic deceleration surface connecting the front end to the rear end of each deployment rod and connected to the heat shield.

9. A control method for a reusable jet thermal protection device at the nose of a reentry vehicle, characterized in that, The method, applied to the thermal protection device as described in any one of claims 1-8, comprises: Extract the gas from the gas collecting bottle to make the pressure in the gas collecting bottle lower than the external air pressure, and close the first solenoid valve; Determine the position of the spacecraft during the ascent of the launch vehicle. When the spacecraft is in the first position, open the first solenoid valve to allow the gas collecting bottle to collect external gas from the gas inlet and outlet, and close the first solenoid valve to store the collected gas in the gas collecting bottle. When determining the reentry mode of the aircraft during a reentry and return mission, the first solenoid valve is controlled to open once or multiple times according to the reentry mode, so that the gas collection bottle ejects the stored gas through the gas inlet or outlet once or multiple times.

Images