Cooling system and aircraft

Abstract

The invention relates to the technical field of spacecrafts, in particular to a cooling system and an aircraft. The system is applied to an aircraft, an aircraft body of the aircraft is formed by connecting a main body on the inner side and a skin on the outer side, a flow channel extending from the head of the aircraft body to the tail of the aircraft body is arranged between the main body and the skin, and the aircraft body is provided with an air film hole penetrating through the main body and the skin; the cooling system is arranged in an inner cavity of the machine body and comprises a storage assembly, a cooling assembly and a circulating assembly, the storage assembly is used for storing a cooling medium, and the cooling assembly is used for cooling the cooling medium; the circulating assembly comprises a power pump and a turbine, and the power pump is used for pressurizing a cooling medium and pumping the pressurized cooling medium into the flow channel from the head of the machine body; an air inlet of the turbine is communicated with the runner between the tail part and the neck part of the machine body; and an air outlet of the turbine is communicated with one end of the air film hole in the inner cavity of the machine body. The system can quickly reduce the temperature of the head of the aircraft.

Description

Technical Field

[0001] The present application relates to the technical field of space vehicles, and particularly to a cooling system and a vehicle. Background Art

[0002] Near space refers to the airspace 20 - 100 kilometers above the ground. This airspace includes the stratosphere region of the atmosphere (referring to the airspace 18 to 55 kilometers above the ground), the mesosphere region of the atmosphere (referring to the airspace 55 to 85 kilometers above the ground), and a small part of the thermosphere region (referring to the airspace 85 to 800 kilometers above the ground), and most of its components are homogeneous atmosphere. A high - speed near - space vehicle refers to a vehicle that can only or can make long - term and continuous flights in near space, or a sub - orbital vehicle, or a hypersonic cruise vehicle flying in near space; it has extremely important application value in the field of national defense.

[0003] When a high - speed near - space vehicle flies at high speed, it will generate a large amount of heat due to friction with the atmosphere, which will cause the temperature of the head of the vehicle body to rise sharply; and the material of the head of the vehicle body may fail due to excessive temperature, thus reducing the safety of the vehicle. In related technologies, in order to improve the safety of the vehicle, heat - resistant alloy materials or flame - resistant materials with good performance are often used to protect the head of the vehicle; however, heat - resistant alloy materials have a high density, which will significantly increase the overall mass of the vehicle, and flame - resistant materials are disposable consumables, and the overall processing difficulty is relatively large.

[0004] Therefore, how to quickly cool the head of the vehicle is a technical problem. Summary of the Invention

[0005] Based on this, it is necessary to provide a cooling system and a vehicle that can quickly cool the head of the vehicle for the above - mentioned technical problems.

[0006] In a first aspect, the present application provides a cooling system applied to a vehicle. The vehicle body is composed of an inner main body and an outer skin connected. A flow channel extending from the head to the tail of the vehicle body is provided between the main body and the skin. The vehicle body is provided with air film holes penetrating the main body and the skin; the cooling system is arranged in the inner cavity of the vehicle body, and the system includes a storage component, a cooling component, and a circulation component, where:

[0007] The storage component is used to store a cooling medium, and the cooling component is used to cool the cooling medium;

[0008] The circulation component includes a power pump and a turbine. Among them, the power pump is used to pressurize the cooling medium and pump the pressurized cooling medium into the flow channel from the head of the vehicle body;

[0009] The air inlet of the turbine communicates with the flow channel between the tail and the neck of the body, and the exhaust port of the turbine communicates with one end of the air film hole located in the inner cavity of the body.

[0010] In one embodiment, the output shaft of the turbine is connected to the power shaft of the power pump, and a starter is provided at the air inlet of the turbine.

[0011] In one embodiment, the system further includes an expansion valve. The inlet of the expansion valve is connected to the exhaust port of the turbine, and the output port of the expansion valve communicates with one end of the air film hole located in the inner cavity of the body.

[0012] In one embodiment, on one side of the main body located in the inner cavity of the body, a collector is provided. The collector is a hollow cavity;

[0013] The collector communicates with the outlet of the expansion valve and also communicates with one end of the air film hole located in the inner cavity of the body.

[0014] In one embodiment, the storage assembly includes a storage tank, a filling pipeline, and a pressure relief pipeline, where:

[0015] The storage tank is used to store the cooling medium. The storage tank is connected to the filling pipeline, and the filling pipeline is used to fill the cooling medium into the storage tank; the storage tank is connected to the pressure relief pipeline, and the pressure relief pipeline is used to relieve the pressure of the storage tank;

[0016] The storage tank communicates with the liquid inlet of the power pump through a flow control valve.

[0017] In one embodiment, the storage tank is composed of an inner tank and an outer tank, where:

[0018] The inner tank is located inside the outer tank, and the inner tank is connected to the outer tank through a connecting member;

[0019] The inner tank is used to store the cooling medium, and the space between the inner tank and the outer tank is in a vacuum state.

[0020] In one embodiment, the cooling assembly includes a refrigerator, a circulation pump, a heat insulation box, and an air cooling screen, where:

[0021] The circulation pump and the refrigerator are both arranged in the heat insulation box, and the air cooling screen is arranged in the storage tank;

[0022] The input end of the circulation pump communicates with the return end of the air cooling screen, the output end of the circulation pump communicates with the input end of the refrigerator, and the output end of the refrigerator communicates with the inlet end of the air cooling screen.

[0023] In one embodiment, the cooling medium is liquid ammonia.

[0024] In a second aspect, the present application further provides an aircraft. The fuselage of the aircraft is formed by connecting an inner main body and an outer skin. A flow channel extending from the head to the tail of the fuselage is provided between the main body and the skin.

[0025] The fuselage is provided with film holes penetrating through the main body and the skin.

[0026] The interior of the aircraft is further provided with the cooling system as described in any one of the above first aspects.

[0027] In one embodiment, the film holes are not communicated with the flow channel.

[0028] The cooling assembly can cool down the cooling medium stored in the storage assembly, so that the storage assembly can store and supply the relatively low-temperature cooling medium to the flow channel. The power pump can pump the relatively low-temperature cooling medium stored in the storage assembly into the flow channel from the head position of the aircraft. Since the flow channel is provided between the inner main body and the outer skin of the fuselage of the aircraft and the flow channel extends from the head to the tail of the aircraft, the relatively low-temperature cooling medium can absorb the heat of the head of the fuselage of the aircraft and become a hot gas with a relatively high temperature and pressure, and the hot gas can flow along the flow channel to the tail of the fuselage. Further, since the air inlet of the turbine is communicated with the flow channel between the tail and the neck of the fuselage, the hot gas can enter the air inlet of the turbine and drive the blades of the turbine to rotate and do work; the hot gas further reduces in temperature and pressure after driving the turbine and becomes a neutral gas; the neutral gas is discharged from the turbine to the film holes and is discharged from the film holes to the outside of the fuselage; since the film holes penetrate through the main body and the skin of the fuselage of the aircraft, when the neutral gas is discharged from the film holes to the outside of the fuselage, it will further absorb the heat of the fuselage, thereby further realizing the cooling of the fuselage. That is to say, during the process of the cooling medium from the head of the fuselage to the turbine, the cooling medium can absorb heat and perform the first cooling on the head and neck of the fuselage; and during the process of the neutral gas being discharged from the fuselage through the film holes after being cooled and depressurized by the turbine, the neutral gas can also perform the second cooling on the fuselage. Therefore, the cooling system provided by the present application can quickly realize the cooling of the head of the fuselage, thereby improving the stability and safety of the head of the fuselage of the aircraft. Description of the Drawings

[0029] To more clearly illustrate the technical solutions in the embodiments of the present application or in the related art, the following will briefly introduce the drawings required for use in the description of the embodiments or the related art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0030] Figure 1 It is a schematic cross-sectional view of the head of the body in an embodiment;

[0031] Figure 2 It is a schematic diagram showing the skin and the flow channel structure in an embodiment;

[0032] Figure 3 It is a schematic cross-sectional view of the body showing the structure of the collector and the film holes in an embodiment;

[0033] Figure 4 It is a schematic diagram showing the loop relationship of the components in the cooling system in an embodiment;

[0034] Figure 5 It is a schematic diagram of the structure of the storage component in an embodiment;

[0035] Figure 6 It is a schematic diagram of the structure of the cooling component in an embodiment;

[0036] Figure 7 It is a schematic diagram showing the connection relationship of the circulation components in an embodiment;

[0037] Figure 8 It is a schematic diagram of the state of the circulating medium at each node in the cooling system in another embodiment.

[0038] Reference numerals:

[0039] 100, body; 110, main body; 120, skin; 130, flow channel; 140, collector; 150, film hole; 200, storage component; 210, storage tank; 211, inner box; 212, outer box; 213, connecting piece; 220, filling pipeline; 221, liquid level gauge; 222, check valve; 223, filling port; 230, pressure relief pipeline; 231, back pressure valve; 232, pressure relief valve; 233, mass flow meter; 234, pressure relief port; 240, flow control valve; 300, cooling component; 310, refrigerator; 320, circulation pump; 330, quick connection switch valve; 340, heat insulation box; 350, air cooling screen; 400, circulation component; 410, power pump; 411, liquid inlet; 412, liquid outlet; 420, turbine; 421, air inlet; 422, exhaust port; 430, expansion valve; 440, starter. Detailed implementation manners

[0040] To make the above objects, features, and advantages of the present application more apparent and understandable, the following provides a detailed description of the specific embodiments of the present application in conjunction with the accompanying drawings. Many specific details are set forth in the following description to facilitate a thorough understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the spirit of the present application; it should be understood that the specific embodiments described herein are merely for explaining the present application and are not used to limit the present application.

[0041] In the description of the present application, it should be understood that if terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or positional relationship indicated by these terms is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present application.

[0042] In addition, if terms such as "first" and "second" appear, these terms are only for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In the description of the present application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise specifically and clearly defined.

[0043] In the present application, unless otherwise clearly specified and limited, if terms such as "install", "connect", "couple", "fix", etc. appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0044] In this application, unless otherwise clearly defined and limited, if there is a description such as a first feature being "on" or "under" a second feature, its meaning can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature can be that the first feature is directly above or obliquely above the second feature, or simply means that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature can be that the first feature is directly below or obliquely below the second feature, or simply means that the horizontal height of the first feature is less than that of the second feature.

[0045] It should be noted that if an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there can also be an intermediate element. If an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. If so, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are only for the purpose of illustration and do not represent the only implementation.

[0046] The cooling system provided by the embodiments of this application can be applied to near-space aircraft; here, a necessary structural description of the aircraft applicable to the cooling system will be given first. In an exemplary embodiment, referring to Figure 1 and Figure 2 , the airframe 100 of the aircraft is composed of an inner main body 110 and an outer skin 120 connected. A flow channel 130 extending from the head to the tail of the airframe 100 is provided between the main body 110 and the skin 120, and the airframe 100 is provided with air film holes 150 penetrating through the main body 110 and the skin 120.

[0047] In one of the embodiments, the head of the aircraft can be conical; the material of the head of the aircraft can be selected but not limited to TA15 titanium alloy, and its processing process includes the following steps: ① Use machining to groove on a flat plate to form a flat plate of the main body containing a channel structure (flow channel); ② Weld the skin 120 and the channel structure of the main body 110 to form a plate of the main body 110 containing an internal channel, and the welding methods include but are not limited to brazing and diffusion welding; ③ Stamp the plate of the main body 110 containing the internal channel to form the airframe 100 of the aircraft; ④ The joints are welded firmly to meet the quality requirements of first-class welds. Further, the air film holes 150 provided on the airframe 100 are not communicated with the flow channel 130 to form independent passages respectively.

[0048] Among them, the flow channel 130 can be provided only at the head position of the body 100, or can extend from the head of the body 100 to the neck position of the body 100, or further extend to the tail position of the body 100. Among them, the path of each flow channel 130 can be along the central axis direction of the body 100; however, the path of the flow channel 130 can also be set as a tortuous curve. For example, the flow channel 130 can be a curved path extending from the head of the body 100 to the neck position or the tail position of the body 100 along a spiral path. For the specific position of the extension of the flow channel 130 and the path of the flow channel 130, no specific limitation is made in the embodiments of the present application.

[0049] Further, referring to Figure 1 and Figure 3 , on one side of the main body 110 located in the inner cavity of the body 100, a collector 140 is provided; the collector 140 is a hollow cavity and is fixedly arranged around one side of the main body 110 located in the inner cavity of the body 100; the collector 140 is communicated with one end of the air film hole 150 located in the inner cavity of the body 100.

[0050] In an exemplary embodiment, referring to Figure 4 , the cooling system provided by the present application includes: a storage component 200, a cooling component 300, and a circulation component 400, where:

[0051] The storage component 200 is used to store the cooling medium, and the cooling component 300 is used to cool the cooling medium; the circulation component 400 includes a power pump 410 and a turbine 420. The power pump 410 is used to pressurize the cooling medium and pump the pressurized cooling medium into the flow channel 130 from the head of the body 100; the air inlet 421 of the turbine 420 is communicated with the flow channel 130 between the tail and the neck of the body 100, and the exhaust port 422 of the turbine 420 is communicated with one end of the air film hole 150 located in the inner cavity of the body 100. Further, it should be elaborated that each component of the cooling system provided by the present application is arranged in the inner cavity of the body 100 of the aircraft.

[0052] The cooling assembly 300 can cool down the cooling medium stored in the storage assembly 200, so that the storage assembly 200 can store and supply the cooler cooling medium to the flow channel 130. The power pump 410 can pump the cooler cooling medium stored in the storage assembly 200 from the head position of the aircraft into the flow channel 130. Since the flow channel 130 is opened between the main body 110 on the inner side and the skin 120 on the outer side of the airframe 100 of the aircraft, and the flow channel 130 extends from the head to the tail of the aircraft, the cooler cooling medium can absorb the heat of the head of the airframe 100 of the aircraft and become a hot gas with a higher temperature and pressure, and the hot gas can flow along the flow channel 130 towards the tail of the airframe 100. Further, since the air inlet 421 of the turbine 420 is communicated with the flow channel 130 between the tail and the neck of the airframe 100, therefore, the hot gas can enter the air inlet 421 of the turbine 420 and drive the blades of the turbine 420 to rotate and do work; the hot gas further reduces in temperature and pressure after driving the turbine 420 and becomes a neutral gas; the neutral gas is discharged from the turbine 420 to the air film holes 150 and is discharged from the air film holes 150 to the outside of the airframe 100; since the air film holes 150 penetrate through the main body 110 and the skin 120 of the airframe 100 of the aircraft, therefore, when the neutral gas is discharged from the air film holes 150 to the outside of the airframe 100, it will further absorb the heat of the airframe 100, thereby further realizing the cooling of the airframe 100.

[0053] That is to say, during the process of the cooling medium from the head of the airframe 100 to the turbine 420, the cooling medium can absorb heat to perform the first cooling on the head and neck of the airframe 100; and during the process of the neutral gas being discharged from the airframe 100 through the air film holes 150 after being cooled and depressurized by the turbine 420, the neutral gas can also perform the second cooling on the airframe 100. Therefore, the cooling system provided by the present application can quickly realize the cooling of the head of the airframe 100, thereby improving the stability and safety of the head of the airframe 100 of the aircraft.

[0054] Further, the following will respectively elaborate on each component in the cooling system in detail.

[0055] In one embodiment, referring to Figure 4 and Figure 5 , the storage assembly 200 includes a storage tank 210, a filling pipeline 220, and a pressure relief pipeline 230; wherein, the storage tank 210 is used for storing the cooling medium, the storage tank 210 is communicated with the filling pipeline 220, and the filling pipeline 220 is used for filling the cooling medium into the storage tank 210; the storage tank 210 is communicated with the pressure relief pipeline 230, and the pressure relief pipeline 230 is used for relieving the pressure of the storage tank 210.

[0056] Specifically, the storage tank 210 is composed of an inner tank body 211 and an outer tank body 212; the inner tank body 211 is located inside the outer tank body 212, and the inner tank body 211 and the outer tank body 212 are connected by a connecting member 213; the inner tank body 211 is used to store the cooling medium, and the space between the inner tank body 211 and the outer tank body 212 is in a vacuum state. The inner tank body 211 of the storage tank 210 can be made of aluminum alloy material, and further, carbon fiber can be wound around the outer side of the inner tank body 211, so that the inner tank body 211 is light in mass and has relatively large structural rigidity. The outer tank body 212 of the storage tank 210 can also be processed from aluminum alloy material, and of course, other materials can also be used, which are not specifically limited in the embodiments of the present application.

[0057] The inner tank body 211 and the outer tank body 212 of the storage tank 210 are fixedly connected through the connecting member 213. The connecting member 213 can be processed from epoxy fiberglass with a relatively low thermal conductivity; the connecting member 213 penetrates through the wall of the inner tank body 211 and is connected to the outer tank body 212, and a plurality of connecting members 213 are arranged between the inner tank body 211 and the outer tank body 212, so that the inner tank body 211 and the outer tank body 212 can maintain relative stability. Since the space between the inner tank body 211 and the outer tank body 212 is in a vacuum state or a state close to vacuum, the heat exchange efficiency between the inner tank body 211 and the outside world is relatively low. Moreover, the connecting member 213 also uses a material with a relatively low thermal conductivity, so that the cooling medium stored in the inner tank body 211 can maintain a relatively low temperature under the action of the cooling system.

[0058] Further, referring to Figure 4 and Figure 5 , the filling pipeline 220 includes a check valve 222 and a liquid level gauge 221; a filling port 223 is opened on the storage tank 210, the filling port 223 is connected to the outlet end of the check valve 222, and the liquid level gauge 221 is arranged at the inlet end of the check valve 222. The external cooling medium can enter the storage tank 210 through the check valve 222 and the filling port 223. The check valve 222 can prevent the backflow of the cooling medium, thereby improving the efficiency of filling the cooling medium into the storage tank 210; the liquid level gauge 221 can detect the liquid level of the cooling medium in the storage tank 210. It should be noted that the cooling medium can be liquid or gas at room temperature; in an example of the embodiments of the present application, the cooling medium uses liquid ammonia; ammonia is gaseous at room temperature and atmospheric pressure, but the boiling point of ammonia gas is -33.5°C and the melting point is -77.73°C. When the temperature drops to a certain extent, ammonia gas can be liquefied into liquid ammonia. Of course, other media can also be used as the cooling medium, which are not specifically limited in the embodiments of the present application.

[0059] Further, referring to Figure 4 and Figure 5, the pressure relief pipeline 230 includes a back pressure valve 231, a pressure gauge, a pressure relief valve 232, and a mass flow meter 233. Among them, the storage tank 210 is provided with a pressure relief port 234. The inlet end of the mechanical pressure relief valve 232 is connected to the pressure relief port 234 of the storage tank 210. The outlet end of the pressure relief valve 232 is connected to the inlet end of the back pressure valve 231, and the outlet end of the pressure relief valve 232 is connected to the mass flow meter 233; the back pressure valve 231 is also connected with a pressure gauge. When the pressure in the storage tank 210 is relatively high (for example, exceeding the set pressure threshold), the pressure relief valve 232 and the back pressure valve 231 can be opened, so as to realize the pressure relief of the storage tank 210 and ensure the safety of the storage tank 210.

[0060] In one embodiment, referring to Figure 5 and Figure 6 , the cooling assembly 300 includes a refrigerator 310, a circulation pump 320, a heat insulation box 340, a quick-connect switch valve 330, and an air-cooled screen 350; among them, the circulation pump 320 and the refrigerator 310 are both arranged in the heat insulation box 340, and the air-cooled screen 350 is arranged in the storage tank 210; the input end of the circulation pump 320 communicates with the return end of the air-cooled screen 350, the output end of the circulation pump 320 communicates with the input end of the refrigerator 310, and the output end of the refrigerator 310 communicates with the inlet end of the air-cooled screen 350.

[0061] Specifically, referring to Figure 5 and Figure 6 , the air-cooled screen 350 is composed of a bent connecting pipeline. The connecting pipeline is made of a material with a relatively high thermal conductivity, so as to improve the heat exchange efficiency of the air-cooled screen 350. One end of the air-cooled screen 350 is connected to the inlet of the refrigerator 310 through a quick-connect switch valve 330. The outlet of the refrigerator 310 is connected to the inlet of the circulation pump 320. The outlet of the circulation pump 320 and the other end of the air-cooled screen 350 are connected through a quick-connect switch valve 330. A mass flow meter 233 is also connected between the outlet of the circulation pump 320 and the air-cooled screen 350. Further, the heat insulation box 340 is fixedly connected to the inner cavity of the airframe 100 of the aircraft, and the refrigerator 310, the circulation pump 320, the quick-connect switch valve 330, and the mass flow meter 233 are all arranged in the heat insulation box 340 to reduce the heat exchange with the outside.

[0062] The fluid stored in the circulation pump 320 is a fluid for cooling, such as a hydrocarbon refrigerant; under the action of the circulation pump 320, the fluid can circulate between the air-cooled screen 350 and the refrigerator 310; the fluid conducts the heat of the cooling medium in the storage tank 210, and the fluid cooled by the refrigerant enters the air-cooled screen 350 again; the continuous circulation of the fluid cools the circulating medium; and because the heat exchange efficiency between the storage tank 210 and the outside is relatively low, the cooling medium in the storage tank 210 can be maintained at a relatively low temperature for a long period.

[0063] In one embodiment, the storage tank 210 is communicated with the liquid inlet 411 of the power pump 410 through a flow control valve 240; the inlet end of the flow control valve 240 is communicated with the inner tank 211 of the storage tank 210, the outlet end of the flow control valve 240 is communicated with the liquid inlet 411 of the power pump 410, and the liquid outlet 412 of the power pump 410 is communicated with the flow channel 130 at the head position of the airframe 100 of the aircraft.

[0064] Referring to Figure 7 , the output shaft of the turbine 420 is connected to the power shaft of the turbine 420 pump, and a starter 440 is provided at the air inlet 421 of the turbine 420. Among them, the air inlet 421 of the turbine 420 is communicated with the flow channel 130 between the tail and the neck of the airframe 100, and is used to introduce the heated and pressurized hot gas (cooling medium) in the flow channel 130 to drive the blades of the turbine 420 to rotate.

[0065] Referring to Figure 4 , the circulation assembly 400 further includes an expansion valve 430, and the exhaust port 422 of the turbine 420 is communicated with the inlet end of the expansion valve 430, and the outlet end of the expansion valve 430 is communicated to the air film hole 150, and is used to discharge the neutral gas after being cooled and depressurized by the turbine 420 out of the airframe 100 through the air film hole 150.

[0066] Furthermore, the expansion valve 430 can adjust the flow rate of the gas output to the air film through the expansion valve 430 according to the external heat flux, where the external heat flux is the high-temperature heat flux formed by the friction between the airframe 100 and the atmosphere during the flight of the aircraft. Among them, the expansion valve 430 can further reduce the temperature and pressure of the neutral gas discharged from the exhaust port 422 of the turbine 420, thereby improving the efficiency of the second cooling of the airframe 100 by the neutral gas.

[0067] Furthermore, referring to Figure 4 and Figure 7 , a starter 440 is provided at the air inlet 421 of the turbine 420, and the starter 440 is used to start the turbine 420; the starter 440 can be an electric starter 440 or a powder starter 440, and is used to generate high-temperature and high-pressure gas to form an initial drive for the turbine 420; since the power pump 410 is driven by the drive shaft of the turbine 420, therefore, after the turbine 420 is initially started by the starter 440, the power pump 410 starts to work, thereby pumping the cooling medium in the storage tank 210 into the flow channel 130; the cooling medium absorbs heat and warms up to become hot gas in the flow channel 130, and the hot gas then enters the air inlet 421 of the turbine 420, thereby realizing circulation to maintain the continuous operation of the turbine 420 and the power pump 410.

[0068] Furthermore, referring to Figure 2 and Figure 4, on one side of the inner cavity of the body 100 where the main body 110 is located, a collector 140 is provided. The collector 140 is a hollow cavity; the collector 140 is communicated with the outlet of the expansion valve 430 and is also communicated with one end of the air film hole 150 located in the inner cavity of the body 100.

[0069] Specifically, the collector 140 is a hollow cavity and is fixedly arranged around one side of the main body 110 located in the inner cavity of the body 100. The collector 140 is communicated with the outlet end of the expansion valve 430. At the same time, the collector 140 is communicated with one end of the air film hole 150 located in the inner cavity of the body 100. The neutral gas discharged through the expansion valve 430 is buffered in the collector 140. The collector 140 is conducive to the uniform distribution of the neutral gas. Then the neutral gas is discharged from the collector 140 to the air film hole 150 to realize the secondary cooling of the body 100. Further, since the air film hole 150 opened on the body 100 is not communicated with the flow channel 130, the cooling medium in the flow channel 130 is prevented from directly leaking from the air film hole 150.

[0070] Further, referring to Figure 4 , a temperature and pressure component is provided on the body 100 to detect the temperature data and pressure data of the body 100. The temperature and pressure component includes a temperature sensor and a pressure sensor; multiple groups of temperature and pressure components can be provided in the body 100. For example, one group of temperature and pressure components can be respectively provided at the head position, neck position, and tail position of the inner cavity of the body 100. And, on the connecting pipeline between the power pump 410 and the flow channel 130 at the head position of the body 100, one group of temperature and pressure components is also provided to detect the pressure data and temperature data of the cooling medium input into the flow channel 130. One group of temperature and pressure components is also provided at the air inlet 421 of the turbine 420 to detect the pressure data and temperature data of the gas input from the flow channel 130 into the turbine 420. At the inlet end of the expansion valve 430, one group of temperature and pressure components is also provided to detect the pressure data and temperature data of the neutral gas output by the turbine 420. One group of temperature and pressure components is provided in the inner box body 211 of the storage tank 210 to detect the pressure data and temperature data of the cooling medium stored in the storage tank 210.

[0071] In one embodiment, the overall parameters of the aircraft including the above cooling system are deduced and calculated. It is set that the flight time of the aircraft in the atmosphere is , the aircraft generates heat due to friction with the atmosphere during flight, and its average heat flux density is , the high-temperature area of the aircraft head is , then the heat absorbed by the aircraft during flight in the atmosphere can be expressed by formula (1), where:

[0072] , formula (1).

[0073] Furthermore, the heat absorbed by the aircraft during flight in the atmosphere Part of it is the heat capacity of the aircraft itself, another part is dissipated by radiative heat dissipation, and the remaining heat is absorbed by the cooling medium in the cooling system in two times and discharged from the airframe 100. Then the heat absorbed by the cooling medium (assuming the cooling medium is ammonia here) can be expressed by formula (2):

[0074] , formula (2). Wherein, is the specific heat capacity of the aircraft head; is the mass of the aircraft head; are the stable temperature and the pre-flight temperature of the aircraft head respectively; is the surface emissivity of the aircraft material; is the blackbody radiation constant.

[0075] Furthermore, the pressure of ammonia in the storage tank 210 is set as , and the temperature is . After the flow control valve 240 is opened, the liquid ammonia enters the power pump 410. The pressure of the liquid ammonia at the liquid outlet 412 of the power pump 410 is , and the temperature is , and the enthalpy value is ; then the liquid ammonia enters the flow channel 130 from the aircraft head position; after the liquid ammonia completes the first heat absorption, the pressure of the formed ammonia gas (hot gas) is , and the temperature is , and the enthalpy value is . Then the high-temperature and high-pressure ammonia gas (hot gas) enters the turbine 420 to do work. The pressure of the ammonia gas (neutral gas) at the exhaust port 422 of the turbine 420 is , and the temperature is ; after the neutral gas discharged from the turbine 420 passes through the expansion valve 430, the pressure of the ammonia gas is , and the temperature is , and the enthalpy value is . The neutral gas discharged from the expansion valve 430 enters the collector 140 again and enters the cooling channel of the air film hole 150. The neutral gas absorbs heat again and is discharged outside the airframe 100. Finally, the pressure of the discharged ammonia gas is , and the temperature is , and the enthalpy value is .

[0076] Then the enthalpy difference of the ammonia absorbing heat twice can be expressed by formula (3):

[0077] , formula (3).

[0078] According to the law of conservation of energy, the total mass of ammonia required can be expressed by formula (4), where:

[0079] , formula (4).

[0080] Then the flow rate of ammonia required can be expressed by formula (5), where: , formula (5).

[0081] Furthermore, set the length of the flow channel 130 at the head position of the aircraft tail , and the equivalent diameter is , then the resistance coefficient of ammonia in the flow channel 130 can be expressed by formula (6), where:

[0082] , formula (6); is the Reynolds number of ammonia at the corresponding temperature and pressure.

[0083] The flow of ammonia in the flow channel 130 at the head position of the aircraft is turbulent flow, and the Nusselt numbers corresponding to ammonia in different states are shown by formula (7) and formula (8) respectively, where:

[0084] , formula (7) - gaseous state;

[0085] , formula (8) - liquid state;

[0086] Among them, is the temperature of ammonia in the flow channel 130 at the head of the aircraft; is the wall temperature of the flow channel 130 at the head of the aircraft; is the Prandtl number of ammonia at the corresponding temperature and pressure.

[0087] Furthermore, the total heat transfer coefficient of the ammonia flow in the flow channel 130 at the head of the aircraft can be expressed by formula (9):

[0088] , formula (9); is the thermal conductivity of ammonia at the corresponding temperature and pressure.

[0089] The total heat transfer area of the ammonia flow channel 130 at the head of the aircraft can be expressed by formula (10):

[0090] , formula (10).

[0091] The total pressure drop of the flow channel 130 at the head of the aircraft is expressed by formula (11): , formula (11); is the flow rate of ammonia at the corresponding temperature and pressure.

[0092] Based on the total heat transfer area, total pressure drop, equivalent diameter of the flow channel 130, and the length of the flow channel 130 at the head of the aircraft, the detailed structure of the flow channel 130 at the head of the aircraft can be obtained.

[0093] Furthermore, as shown in Figure 4 or Figure 7 , temperature sensors (T) and pressure sensors (P) are provided at the key parts of the aircraft and at the inlets and outlets of each component in the cooling system to continuously detect temperature data and pressure data. The flow rate of ammonia in the cooling system can be adjusted through the flow control valve 240 and the expansion valve 430 to ensure that the temperature of the aircraft body 100 is in a normal state.

[0094] In one embodiment, it is set that the flight time of the aircraft in the atmosphere is 1200 s. During the flight of the aircraft, heat is generated by friction with the atmosphere, and its average heat flux density is 400 kW. The area of the high-temperature region at the head of the aircraft is , then the heat absorbed by the aircraft during flight in the atmosphere can be calculated from formula (1) , where: .

[0095] In this embodiment, the heat absorbed by the aircraft during flight in the atmosphere is partly the heat capacity of the aircraft itself, partly dissipated by radiation, and the remaining heat is absorbed by ammonia. Then, the heat absorbed by the cooling medium ammonia can be calculated from formula (2) :

[0096] .

[0097] In this embodiment, it is set that the pressure of ammonia in the inner box body 211 of the storage tank 210 is , the temperature is 240 K. After the flow control valve 240 is opened, liquid ammonia enters the power pump 410. The pressure of the liquid ammonia at the liquid outlet 412 end of the power pump 410 is 6 MPa, and the temperature is 242 K. The enthalpy value can be found in Table (1); then the liquid ammonia enters the flow channel 130 at the head of the aircraft for the first heat absorption, and the liquid ammonia becomes a hot gas with a higher temperature and higher pressure. At this time, the pressure of the ammonia gas is 5.7 MPa, and the temperature is 780 K, and the enthalpy value is It can be found in Table (1); then, the high-temperature and high-pressure ammonia gas enters the turbine 420 to do work, and the pressure of the ammonia gas at the exhaust port 422 of the turbine 420 is 1 MPa, and the temperature is 585 K. After passing through the expansion valve 430, the pressure of the ammonia gas is 0.3 MPa, and the temperature is 465 K, and the enthalpy value can be found in Table (1); the neutral gas discharged from the expansion valve 430 enters the collector 140 again and enters the cooling channel of the gas film hole 150; the neutral gas absorbs heat for the second time in the gas film hole 150 and is then discharged outside the body 100. Finally, the pressure of the discharged ammonia gas is 0.2 MPa, and the temperature is 800 K, and the enthalpy value can be found in Table (1).

[0098] The enthalpy difference of ammonia during the two heat absorptions can be calculated by formula (3): . According to the law of conservation of energy, the total mass of ammonia required can be calculated by formula (4): . The flow rate of ammonia required can be calculated by formula (5): .

[0099] In this embodiment, the length of the flow channel 130 at the head of the aircraft is 500 mm, and the equivalent diameter is 1.33 mm. Then, the resistance coefficient of ammonia in the flow channel 130 can be calculated by formula (6): .

[0100] The ammonia in the flow channel 130 at the head of the aircraft is in turbulent flow, and the Nusselt numbers of ammonia in different states can be calculated by formula (7) and formula (8), where:

[0101] ;

[0102] .

[0103] Furthermore, the total heat transfer coefficient of ammonia flowing in the flow channel 130 at the head of the aircraft can be calculated by formula (9): .

[0104] The total heat transfer area of the flow channel 130 at the head of the aircraft can be calculated by formula (10):

[0105] .

[0106] Furthermore, the total heat transfer area of the flow channel 130 at the head of the aircraft is obtained. .

[0107] The total pressure drop of the flow channel 130 at the head of the aircraft can be calculated by formula (11), where:

[0108] .

[0109] The calculation results of each item in this embodiment are summarized in Table (2). The schematic relationship between the temperature data and pressure data in the total cooling system calculated in this embodiment is as Figure 8 shown.

[0110] Table (1)

[0111]

[0112] Table (2)

[0113]

[0114] Unless otherwise specifically stated, the relative arrangements, numerical expressions, and numerical values of the components and steps described in these embodiments do not limit the scope of the present invention. At the same time, it should be understood that, for the sake of convenience of description, the dimensions of the various parts shown in the drawings are not drawn in actual proportional relationships.

[0115] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0116] The above-described embodiments only represent several implementation manners of the present application. Their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent of the present application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A cooling system, characterized in that: Applied to an aircraft, the aircraft body is composed of an inner main body and an outer skin connected together, a flow channel extending from the head to the tail of the body is provided between the main body and the skin, and the body is provided with air film holes penetrating the main body and the skin; the cooling system is provided in the inner cavity of the body, and the system includes a storage component, a cooling component and a circulation component, wherein: The storage component is used to store the cooling medium, and the cooling component is used to cool the cooling medium; The circulation assembly includes a power pump and a turbine, wherein the power pump is used to pressurize the cooling medium and pump the pressurized cooling medium into the flow channel from the head of the machine body; The air inlet of the turbine is communicated with the flow channel between the tail and the neck of the body, and the exhaust port of the turbine is communicated with one end of the air film hole located in the inner cavity of the body.

2. The system according to claim 1, characterized in that The output shaft of the turbine is connected to the power shaft of the power pump, and a starter is provided at the air inlet of the turbine.

3. The system according to claim 2, characterized in that The system further comprises an expansion valve, the inlet of the expansion valve is connected to the exhaust port of the turbine, and the output port of the expansion valve is communicated with one end of the air film hole located in the inner cavity of the body.

4. The system according to claim 3, characterized in that A collector is provided on one side of the main body located in the inner cavity of the machine body, and the collector is a hollow cavity; The collector is communicated with the outlet of the expansion valve, and is communicated with one end of the air film hole located in the inner cavity of the body.

5. The system according to claim 1, characterized in that The storage assembly includes a storage tank, a filling pipeline and a pressure relief pipeline, wherein: The storage tank is used to store the cooling medium, the storage tank is connected to a filling pipeline, the filling pipeline is used to fill the cooling medium into the storage tank; the storage tank is connected to a pressure relief pipeline, the pressure relief pipeline is used to relieve the pressure of the storage tank; The storage tank is communicated with the liquid inlet of the power pump through a flow control valve.

6. The system according to claim 5, characterized in that The storage box is composed of an inner box body and an outer box body, wherein: The inner box is located inside the outer box, and the inner box is connected to the outer box via a connecting piece; The inner box is used to store the cooling medium, and the space between the inner box and the outer box is in a vacuum state.

7. The system according to claim 6, characterized in that The cooling assembly includes a refrigerator, a circulating pump, a heat insulation box and an air cooling screen, wherein: The circulating pump and the refrigerator are both arranged in the heat-insulating box, and the air-cooling shield is arranged in the storage box; The input end of the circulation pump is connected to the return end of the air-cooled screen, the output end of the circulation pump is connected to the input end of the refrigerator, and the output end of the refrigerator is connected to the inlet end of the air-cooled screen.

8. The system according to any one of claims 1 to 7, characterized in that: The cooling medium is liquid ammonia.

9. An aircraft, characterized in that: The fuselage of the aircraft is composed of an inner main body and an outer skin connected together, and a flow channel extending from the head to the tail of the fuselage is provided between the main body and the skin; The body is provided with an air film hole penetrating the main body and the skin; The interior of the aircraft is also provided with a cooling system as described in any one of claims 1-8.

10. The aircraft according to claim 9, characterized in that The air film hole is not connected to the flow channel.

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