Adaptive aircraft-engine integrated thermal management system based on third flow and fuel heat sink

Abstract

The present application discloses an adaptive flight-engine integrated thermal management system based on a third flow and a fuel heat sink, which is mainly used in supersonic aircraft. The system includes a closed air circulation subsystem, a fuel heat management subsystem and a three-duct variable cycle engine subsystem; the three-duct variable cycle engine subsystem has three-duct, double-duct and single-duct working modes. When the flight Mach number is lower than 1.5, the three-duct variable cycle engine subsystem opens the third duct, cools the thermal load of the onboard electronic equipment and the high-temperature return oil through the third duct radiator, and stores the excess heat sink capacity in the cold storage tank; when the flight Mach number is higher than 1.5, the third duct is closed, and the low-temperature fuel in the cold storage tank is used as a heat sink to achieve airborne thermal load cooling. The present application makes full use of the low-temperature air heat sink capacity of the third duct and the fuel heat storage capacity to achieve time-space adaptive flight-engine integrated thermal management, and effectively improve the cooling performance of the thermal management system under different flight modes.

Description

Technical Field

[0001] The present application relates to the field of aerospace, and specifically to an adaptive aircraft-engine integrated thermal management system based on a third flow and a fuel heat sink. Background Art

[0002] Aviation vehicles are developing towards high maneuverability, wide speed range, wide airspace, high stealth, etc., which poses higher challenges to aircraft thermal management technology. From the perspective of aircraft onboard, on the one hand, a large number of composite materials are used in the aircraft structure, resulting in a continuous reduction in the heat dissipation path of the heat generated inside the aircraft; on the other hand, aircraft operations require more high-power airborne equipment to work (such as radar, directed energy weapons, etc.), resulting in a significant increase in the heat generated by airborne equipment. From the perspective of the engine, achieving high-performance power requirements such as wide speed range, wide airspace and combat maneuverability will lead to more heat generated in the engine combustion chamber and rotating parts during operation. However, the traditional thermal management system separates the design of the airborne thermal management system from the engine thermal management system, and realizes the coupling of the two thermal management systems by setting the fuel temperature boundary, which results in a low margin of the thermal management system design index and increases the difficulty of designing the aircraft and engine thermal management systems. Aircraft engine integrated thermal management can effectively break the temperature boundary barrier, and functionally realize the comprehensive distribution and regulation of aircraft and engine heat and heat sink, and structurally realize a more compact and lightweight design to meet the requirements of future high-performance aircraft development.

[0003] Integrated thermal management of aircraft and engines refers to the comprehensive and unified deployment of aircraft thermal management and engine thermal management in terms of working sequence and spatial structure, which can not only realize the design of compact, lightweight and efficient thermal management system, but also improve the heat dissipation potential of the thermal management system to a greater extent. In the face of flight missions in a wide speed range and wide airspace, the use of adaptive control technology can better solve the problem of time-varying multi-operating conditions, that is, for different flight conditions, the thermal management system can automatically adjust the system working mode, select the best thermal management path and heat sink, and achieve the maximum heat dissipation capacity and highest working efficiency of the system.

[0004] Future supersonic fighters need to have characteristics such as wide speed range, wide airspace, high stealth and high maneuverability. This requires more electronic equipment to achieve higher flight performance, which greatly increases the heat load. On the other hand, in order to meet the higher stealth requirements, a large number of composite materials are used and the aircraft air intake is reduced, which greatly limits the heat dissipation path. The contradiction between the increasing heat load and the reduced heat dissipation capacity in thermal management issues is becoming more and more prominent. The traditional thermal management system that relies on air and fuel as heat sinks can no longer meet the heat dissipation capacity requirements, and new heat dissipation methods need to be adopted to alleviate the heat dissipation pressure. At present, the more common technical means include: using a closed-loop air system to achieve comprehensive control of airborne thermal management and various engine states through a compact structure; using a variable cycle engine structure to achieve changes in the engine flight state under a wide speed range by changing the internal geometry of the engine. In addition, consumable heat sinks, energy storage materials, cold storage structures and duct structures also show good heat dissipation potential. Among them, the cold storage structure includes a cold storage tank, etc., that is, when the system heat dissipation capacity is sufficient, more fuel working fluid is cooled through the heat dissipation path, and the insulation structure is used to recover and store the low-temperature fuel heat sink working fluid. When the system heat dissipation capacity is insufficient, the low-temperature fuel working fluid in the cold storage tank is led out and used in the link that needs further cooling in the thermal management system, so as to achieve the cooling and heat transfer of the high-temperature working fluid in the thermal management system in a short time; the duct structure includes a duct radiator, etc., and adopts a three-duct structure to improve the engine working efficiency by increasing the engine bypass ratio. At the same time, on the one hand, the air temperature of the third duct is lower than the temperature of the outer duct air flow of the traditional turbofan engine. The low-temperature air in the duct is used as a heat sink to cool the high-temperature heat sink working fluid in the thermal management system. On the other hand, the heat exchange in the duct structure does not affect the aerodynamic layout and stealth characteristics of the engine, and increases the engine heat dissipation path. In view of this, the use of more efficient and lightweight system designs, such as variable cycle engine systems, closed air circulation systems, duct structures, etc., is more effective in improving the heat dissipation capacity of the thermal management system.

[0005] The variable cycle engine is an adaptive engine that can adapt to different flight mission conditions by changing the size and geometry of its own structural components. By changing its own thermodynamic cycle parameters, the engine can operate with higher thrust and lower fuel consumption in a wide range of speed and airspace. Based on the variable cycle engine using the third bypass structure, the engine structure can be further changed under different flight conditions to achieve a comprehensive improvement in the engine's thermal management capabilities and fuel economy.

[0006] Different from the traditional airborne electromechanical system with independent design of each structure, the closed air circulation system has great advantages: on the one hand, the independent systems are integrated to reduce the system components and mass, reduce the airborne compensation loss, and at the same time, the use of multiple components on a coaxial basis can maximize the compactness of the spatial structure; on the other hand, the system integrates the functions of emergency power unit, auxiliary power unit, environmental control system and thermal management system to realize adaptive power and thermal function management; in addition, the system can reduce the use of ram air and improve the stealth capability of the aircraft.

[0007] Therefore, combining the heat dissipation advantages of the above systems and structures, a time-space adaptive aircraft-engine integrated thermal management system based on the third flow and fuel heat sink is invented, and the aircraft-engine integrated thermal management design is carried out based on the combat needs of hypersonic fighter jets, so as to realize the integrated management of heat from the aircraft to the engine thermal management system, and at the same time, it can ensure the normal operation and heat dissipation needs of the onboard equipment of the fighter jet in the supersonic cruise state, realize the integrated thermal management of the aircraft and the engine, and lay the foundation for the comprehensive energy management of the next generation of fighter jets. Summary of the invention

[0008] The present application discloses an adaptive aircraft-engine integrated thermal management system based on a third flow and a fuel heat sink. The closed air circulation subsystem cools the engine bleed air, and the obtained low-temperature and low-pressure gas is used to absorb the heat generated by the airborne equipment; the fuel thermal management subsystem uses the fuel as a heat sink to cool the aircraft's onboard thermal load and the heat generated inside the engine; the three-duct variable cycle engine subsystem uses the duct radiator to dissipate the heat absorbed from the air and fuel through the low-temperature duct air to the combustion chamber or the external environment.

[0009] To achieve the above objectives, this application discloses the following solutions:

[0010] Adaptive flight engine integrated thermal management system based on third flow and fuel heat sink, including: closed air cycle subsystem, fuel thermal management subsystem and three-bypass variable cycle engine subsystem;

[0011] The closed air circulation subsystem cools the engine bleed air, and the obtained low-temperature and low-pressure gas is used to absorb the heat generated by the airborne equipment and is transferred to the fuel and the engine duct structure;

[0012] The fuel thermal management subsystem uses fuel as a heat sink to cool the aircraft's onboard thermal load and the heat generated inside the engine; the cold storage tank in the fuel thermal management subsystem collects low-temperature return oil in the three-duct working mode and is used to cool the aircraft's onboard thermal load in other duct working modes;

[0013] The three-bypass variable cycle engine subsystem uses a ducted radiator to dissipate the heat absorbed from the air and fuel into the combustion chamber or the external environment through low-temperature ducted air. The three-bypass variable cycle engine subsystem ensures that the aircraft thermal management system operates stably within the flight Mach number range of 0 to 3.2 by adaptively adjusting the working mode, thereby enhancing the heat dissipation capacity of the thermal management system.

[0014] Preferably, the closed air circulation subsystem includes: a second ducted radiator, a third ducted radiator-air, a high-temperature liquid-air heat exchanger, a low-temperature liquid-air heat exchanger, a recuperator, a fuel-air heat exchanger, a cooling turbine, a compressor, a power turbine and an air circuit valve.

[0015] Preferably, the fuel thermal management subsystem includes: a fuel tank, a liquid fuel heat exchanger, a hydraulic fuel heat exchanger, a lubricating oil radiator, a fuel boost pump, a main pump regulator, a booster pump, a nozzle oil source pump, a nozzle booster regulator, a fuel and lubricating oil radiator, a booster fuel and lubricating oil radiator, a booster distributor, a third duct radiator-fuel, a cold storage tank, an oil circuit valve, a metering valve, a hydraulic actuator, a first control valve, a second control valve and a third control valve.

[0016] Preferably, the three-duct variable cycle engine subsystem includes: a fan, a low-pressure compressor, a high-pressure compressor, a combustion chamber, a high-pressure turbine, a low-pressure turbine, an afterburner, an engine nozzle and a third duct radiator-bleed air.

[0017] Preferably, the working method of the closed air circulation subsystem includes:

[0018] The engine bleed air is dissipated through the second ducted radiator, compressed by the compressor, cooled by the third ducted radiator, high-temperature liquid-air heat exchanger and regenerator, and then enters the cooling turbine for expansion cooling. The obtained low-temperature and low-pressure gas is used to absorb the heat generated by the airborne equipment and transmitted to the fuel and engine duct structure to ensure that the temperature of the airborne equipment and the cabin will not overheat.

[0019] Preferably, the working method of the fuel thermal management subsystem includes:

[0020] With the fuel as the heat sink, after the fuel flows out of the tank, it collects the heat load on board the aircraft and the heat generated inside the engine. Part of the fuel is burned in the combustion chamber to dissipate the heat, and the other part is dissipated through the duct radiator during the oil return process. In addition, in the three-duct working mode, a cold storage tank is used to collect low-temperature return oil, and used as a heat sink to cool the onboard heat load in other working modes.

[0021] Preferably, the three-bypass variable cycle engine subsystem working method includes:

[0022] The heat absorbed by the air and fuel is dissipated to the combustion chamber or the external environment through the low-temperature ducted air through the second ducted radiator, the third ducted radiator-air and the third ducted radiator-fuel; at the same time, the air bleed from the high-pressure compressor outlet is cooled to cool the turbine casing; the low-temperature air after the fan is used to cool the engine casing structure; in addition, the lower third ducted air temperature and the avoidance of ram air intake openings help to improve the infrared stealth of the aircraft.

[0023] The beneficial effects of this application are:

[0024] (1) It realizes the integrated management of the thermal management system in terms of structure and function, and also realizes the adaptive control of the thermal management system;

[0025] (2) Under the premise of meeting the stealth requirements of the aircraft, the low-temperature ducted air in the third duct structure can be used to achieve multi-path transmission and dissipation of heat to meet the increasing heat dissipation needs; while increasing the heat dissipation paths and heat dissipation, the flow rate of fuel as a heat sink can be reduced, thereby improving the economic benefits of fuel;

[0026] (3) The method of using a cold storage tank to store low-temperature heat sinks can be adaptively called in different flight missions to enhance the adaptability of the thermal management system;

[0027] (4) The use of a closed air circulation system can reduce the mass and volume of the onboard system while meeting the heat dissipation requirements of the onboard equipment and the cabin;

[0028] (5) Make full use of the strong adaptability and large heat dissipation potential of the adaptive variable cycle engine, so that the fighter can pursue a working state with low fuel consumption and high heat dissipation performance in a wide speed range and wide airspace. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solution of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0030] Figure 1 This is a schematic diagram of the structure of the adaptive aircraft-engine integrated thermal management system based on the third flow and fuel heat sink in this application.

[0031] Description of Reference Numerals

[0032] 101. Second ducted radiator; 102. Third ducted radiator-air; 103. High-temperature liquid-air heat exchanger; 104. Low-temperature liquid-air heat exchanger; 105. Regenerator; 106. Cooling turbine; 107. Compressor; 108. Power turbine; 109. Fuel-air heat exchanger; 110. Gas valve; 201. Fuel tank; 202. Liquid fuel heat exchanger; 203. Hydraulic fuel heat exchanger; 204. Lubricating oil fuel radiator; 205. Fuel booster pump; 206. Main pump regulator; 207. Afterburner pump; 208. Nozzle oil source pump; 209. Nozzle afterburner regulator; 2 10a, fuel and lubricating oil radiator; 210b, afterburner fuel and lubricating oil radiator; 211, afterburner distributor; 212, third duct radiator - fuel oil; 213, cold storage tank; 214, oil circuit valve; 215, metering valve; 216, hydraulic actuator; 217, first control valve; 218, second control valve; 219, third control valve; 301, fan; 302, low-pressure compressor; 303, high-pressure compressor; 304, combustion chamber; 305, high-pressure turbine; 306, low-pressure turbine; 307, afterburner combustion chamber; 308, engine nozzle; 309, third duct radiator - bleed air. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0034] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0035] Embodiment 1

[0036] In this embodiment 1, if Figure 1 As shown, the adaptive aircraft engine integrated thermal management system based on the third flow and the fuel heat sink includes: a closed air circulation subsystem, a fuel thermal management subsystem and a three-duct variable cycle engine subsystem.

[0037] The following will be combined Figure 1 The composition of each subsystem is described in detail.

[0038] In such Figure 1As shown, the closed air circulation subsystem includes: a second ducted radiator 101, a third ducted radiator-air 102, a high-temperature liquid-air heat exchanger 103, a low-temperature liquid-air heat exchanger 104, a recuperator 105, a cooling turbine 106, a compressor 107, a power turbine 108, a fuel-air heat exchanger 109, and an air circuit valve 110.

[0039] The fuel thermal management subsystem includes: a fuel tank 201, a liquid fuel heat exchanger 202, a hydraulic fuel heat exchanger 203, a lubricating oil radiator 204, a fuel boost pump 205, a main pump regulator 206, a booster pump 207, a nozzle oil source pump 208, a nozzle booster regulator 209, a fuel and lubricating oil radiator 210a, a booster fuel and lubricating oil radiator 210b, a booster distributor 211, a third duct radiator-fuel 212, a cold storage tank 213, an oil circuit valve 214, a metering valve 215, a hydraulic actuator 216, a first control valve 217, a second control valve 218, and a third control valve 219.

[0040] The three-duct variable cycle engine subsystem includes: a fan 301, a low-pressure compressor 302, a high-pressure compressor 303, a combustion chamber 304, a high-pressure turbine 305, a low-pressure turbine 306, an afterburner 307, an engine nozzle 308, and a third duct radiator-bleed air 309.

[0041] Embodiment 2

[0042] In the second embodiment, the operation mode of the adaptive aircraft-engine integrated thermal management system based on the third flow and the fuel heat sink includes:

[0043] The closed air circulation subsystem is mainly divided into two working modes in the process of responding to different flight missions, namely the third duct opening mode and the third duct closing mode; when the third duct is opened, a part of the engine compressor bleed air enters the power turbine to provide power for the rotating shaft, and the cooled air is directly discharged into the environment; the other part of the bleed air is cooled by the second duct radiator and enters the compressor for compression; the compressed air passes through the third duct radiator-air and high-temperature liquid-air heat exchanger in turn to transfer heat to the duct air and liquid cooling medium respectively; in this process, the gas circuit valve is closed and the fuel-air heat exchanger does not participate in air cooling; then it enters the cooling turbine after being cooled by the regenerator, and part of the air cooled by the cooling turbine passes through the low-temperature liquid-air heat exchanger to absorb the heat load of the onboard electronic equipment; part of the air is mixed with the heated high-temperature air and transported to the cabin and the electronic equipment compartment for cooling, and discharged from the aircraft to the external environment; the remaining low-temperature air is heated by the regenerator and mixed with the air flowing through the second duct radiator to realize the closed circulation of the air system. When the third duct is closed, the air compressed by the compressor cannot be cooled through the third duct radiator-air. Therefore, the air path valve is opened in this working state, and the high-temperature air transfers heat to the low-temperature fuel collected in the cold storage tank when the third duct is opened through the fuel-air heat exchanger; then continues to use the high-temperature liquid air heat exchanger for cooling; and then enters the cooling turbine after cooling through the regenerator; the rest of the process is the same as the working mode when the third duct is opened.

[0044] The fuel thermal management subsystem has two working modes during different flight missions, namely afterburner off mode and afterburner on mode. The fuel flows out of the fuel tank as a heat sink, first passing through the liquid fuel heat exchanger to absorb the heat in the liquid cooling medium, realizing the transfer of heat from the air to the fuel; then passing through the hydraulic fuel radiator and lubricating oil fuel radiator in turn, absorbing the heat of the hydraulic system and lubricating oil system; before the heated fuel enters the engine, most of the fuel will flow back to the fuel tank through the return oil pipeline, and the remaining fuel will be driven by the fuel booster pump and divided into three routes. Among them, one path flows to the main pump regulator, and controls the fuel flow to the main combustion chamber through the metering valve. The excess fuel flows back to the front of the boost pump through the return oil pipeline. The fuel after the flow is determined flows to the fuel and lubricating oil radiator, absorbs the heat in the high-temperature lubricating oil used for lubrication and cooling in the engine shaft bearing, and finally flows to the combustion chamber for combustion, thereby realizing the combustion and dissipation of heat; the other path flows to the boost pump, and the fuel pressurized by the boost pump is diverted through the nozzle boost regulator. When the engine turns off the boost mode, all the fuel flows back to the front of the boost pump. When the engine turns on the boost mode, part of the fuel flows back to the front of the boost pump through the return oil pipeline, and the rest of the fuel flows through the boost fuel and lubricating oil radiator to absorb the heat in the high-temperature lubricating oil used for lubrication and cooling in the engine shaft bearing, and then enters the distributor for fuel nozzle flow distribution, and finally flows to the boost combustion chamber for combustion; the last path of fuel flows through the nozzle oil source pump, and finally flows back to the front of the boost pump after passing through the hydraulic actuator. When the fuel temperature after the boost pump is too high, the first control valve opens, and the engine fuel system needs to transfer part of the fuel back to the tank. When the engine is not in the boost state, the fuel will pass through the third duct radiator-fuel during the return process, and a part of the heat load collected in the fuel will be discharged through the duct air to achieve multi-path thermal management; the second control valve opens, and the third control valve closes, and the low-temperature fuel after cooling can enter the cold storage tank for thermal insulation storage. When the third duct of the engine is closed, the oil circuit valve is opened to provide a cold source for the closed air circulation system; after the cold storage tank is full, the second control valve is closed, and the third control valve is opened, and the low-temperature fuel flows directly back to the tank; when the engine is in the boost state, the third duct is closed, and the fuel continues to flow through the third duct radiator-fuel, but cannot be cooled. The second control valve is closed, and the third control valve is opened, and the high-temperature fuel flows directly back to the tank.

[0045] The three-duct variable cycle engine system adopts different modes according to different flight mission requirements: when the flight speed is low, all three ducts are opened, which can increase the bypass ratio, improve the engine endurance and reduce the fuel consumption rate. At the same time, the third duct radiator-fuel, the third duct radiator-air and the second duct radiator can take away the heat in the fuel and air, and improve the working potential of the thermal management system. In addition, since the air temperature in the third duct is low, it mixes with the high-temperature gas at the nozzle, which can reduce the exhaust temperature and improve the stealth performance of the aircraft. When the flight speed is increased to transonic speed, the third duct is closed, the cold storage tank begins to be used, the second duct opening is adjusted, and the afterburner is opened, which can reduce the bypass ratio and improve the engine thrust. At the same time, the second duct radiator works to increase the heat dissipation capacity of thermal management. When the flight speed reaches supersonic speed, the second duct is gradually closed to meet the engine power supply demand and maneuverability requirements. In the engine system, high-pressure gas is drawn out from the outlet of the high-pressure compressor, and after cooling through the third duct radiator-bleed air, the low-temperature gas is transported to the turbine casing for cooling of the turbine guide blades. In addition, the low-temperature air behind the fan is directly introduced into the engine casing compartment for cooling, ensuring that the casing meets the operating temperature requirements.

[0046] Embodiment 3

[0047] In the third embodiment, the operating modes of the adaptive aircraft-engine integrated thermal management system based on the third flow and the fuel heat sink include a three-duct working mode, a dual-duct working mode and a single-duct working mode.

[0048] Embodiment 4

[0049] When the aircraft is in the long-duration cruise phase, the flight Mach number is lower than 1.5, and the engine needs to reduce fuel consumption and provide lower thrust. The three-duct variable cycle engine system opens the third duct to increase the engine bypass ratio; the closed-loop system transfers the continuous heat generated by the onboard electronic equipment to the fuel and the third duct radiator-air for heat dissipation; the engine system only opens the main combustion chamber, and the heat collected in the fuel thermal management system is burned through the main combustion chamber, and the unburned fuel dissipates the heat to the duct air through the third duct radiator-fuel during the oil return process; at the same time, the cold storage tank will store the low-temperature fuel in this mode to provide a cold source for other flight conditions.

[0050] Embodiment 5

[0051] When the aircraft is in takeoff, climbing and other states, the flight Mach number range is greater than 1.5 and less than or equal to 2.2. The engine needs to provide greater thrust while still ensuring a low fuel consumption rate. The three-duct variable cycle engine closes the third duct and only uses the second duct and the core duct to reduce the bypass ratio and increase thrust; the closed air circulation system can not only transfer the heat in the onboard system to the fuel through the high-temperature liquid-air heat exchanger, but also call on the low-temperature fuel in the cold storage tank to absorb and transmit it through the fuel-air heat exchanger; in this mode, the engine turns on the afterburner, and the fuel can burn the collected heat in the main combustion chamber and the afterburner and dissipate it outside the aircraft.

[0052] Embodiment 6

[0053] When the aircraft is in supersonic flight or maneuverable combat state, the flight Mach number is greater than 2.2 and less than or equal to 3.2. The engine needs to meet high performance requirements. The three-duct variable cycle engine only opens the core duct to achieve the maneuverability of the aircraft at a higher fuel consumption rate; the closed air circulation system needs to increase the engine air intake volume to absorb higher heat from onboard equipment. While transferring heat to the fuel through the high-temperature liquid-air heat exchanger, it can also absorb and transfer heat in the fuel-air heat exchanger through the low-temperature fuel in the cold storage tank; the fuel thermal management absorbs more heat and flows to the main combustion chamber and afterburner at a larger flow rate to achieve higher heat dissipation, thereby improving the system's thermal management capabilities under high heat loads.

[0054] The embodiments described above are only descriptions of the preferred methods of the present application, and are not intended to limit the scope of the present application. Without departing from the design spirit of the present application, various modifications and improvements made to the technical solutions of the present application by ordinary technicians in this field should fall within the scope of protection determined by the claims of the present application.

Claims

1. Adaptive flight-engine integrated thermal management system based on third flow and fuel heat sink, characterized by: include: Closed air cycle subsystem, fuel thermal management subsystem and three-duct variable cycle engine subsystem; The closed air circulation subsystem cools the engine bleed air, and the obtained low-temperature and low-pressure gas is used to absorb the heat generated by the airborne equipment and is transferred to the fuel and the engine duct structure; The fuel thermal management subsystem uses fuel as a heat sink to cool the aircraft's onboard thermal load and the heat generated inside the engine; the cold storage tank in the fuel thermal management subsystem collects low-temperature return oil in the three-duct working mode and is used to cool the aircraft's onboard thermal load in other duct working modes; The three-bypass variable cycle engine subsystem uses a ducted radiator to dissipate the heat absorbed from the air and fuel into the combustion chamber or the external environment through low-temperature ducted air. The three-bypass variable cycle engine subsystem ensures that the aircraft thermal management system works stably within the flight Mach number range of 0 to 3.2 by adaptively adjusting the working mode, thereby enhancing the heat dissipation capacity of the thermal management system. The fuel thermal management subsystem includes: a fuel tank, a liquid fuel heat exchanger, a hydraulic fuel heat exchanger, a lubricating oil radiator, a fuel boost pump, a main pump regulator, a booster pump, a nozzle oil source pump, a nozzle booster regulator, a fuel and lubricating oil radiator, a booster fuel and lubricating oil radiator, a booster distributor, a third duct radiator-fuel, a cold storage tank, an oil circuit valve, a metering valve, a hydraulic actuator, a first control valve, a second control valve and a third control valve; The working method of the fuel thermal management subsystem includes: With the fuel as the heat sink, after the fuel flows out of the fuel tank, it collects the heat load on the aircraft and the heat generated inside the engine. Part of the fuel is burned in the combustion chamber to dissipate the heat, and the other part is dissipated through the third duct radiator-fuel during the oil return process; the low-temperature fuel after cooling down in the third duct radiator-fuel enters the cold storage tank for thermal insulation storage, and the oil circuit valve is opened when the third duct of the engine is closed to provide a cold source for the closed air circulation subsystem.

2. The adaptive aircraft-engine integrated thermal management system based on the third flow and the fuel heat sink according to claim 1 is characterized in that: The closed air circulation subsystem includes: a second ducted radiator, a third ducted radiator-air, a high-temperature liquid-air heat exchanger, a low-temperature liquid-air heat exchanger, a recuperator, a fuel-air heat exchanger, a cooling turbine, a compressor, a power turbine and an air circuit valve.

3. The adaptive aircraft-engine integrated thermal management system based on the third flow and the fuel heat sink according to claim 1 is characterized in that: The three-duct variable cycle engine subsystem includes: a fan, a low-pressure compressor, a high-pressure compressor, a combustion chamber, a high-pressure turbine, a low-pressure turbine, an afterburner, an engine nozzle and a third duct radiator-bleed air.

4. The adaptive aircraft-engine integrated thermal management system based on the third flow and the fuel heat sink according to claim 2 is characterized in that: The working method of the closed air circulation subsystem includes: The engine bleed air is dissipated through the second ducted radiator, compressed by the compressor, cooled by the third ducted radiator-air, high-temperature liquid-air heat exchanger and regenerator, and then enters the cooling turbine for expansion cooling. The obtained low-temperature and low-pressure gas is used to absorb the heat generated by the onboard equipment and transmitted to the fuel and engine duct structure to ensure that the temperature of the onboard equipment and the cabin will not overheat.

5. The adaptive aircraft-engine integrated thermal management system based on the third flow and the fuel heat sink according to claim 3 is characterized in that: The three-bypass variable cycle engine subsystem working method includes: The heat absorbed by the air and fuel is dissipated to the combustion chamber or the external environment through the low-temperature ducted air through the second ducted radiator, the third ducted radiator-air and the third ducted radiator-fuel; at the same time, the air bleed from the high-pressure compressor outlet is cooled to cool the turbine casing; the low-temperature air after the fan is used to cool the engine casing structure; in addition, the lower third ducted air temperature and the avoidance of ram air intake openings help to improve the infrared stealth of the aircraft.

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