An experimental apparatus and method for engine thermal management considering aircraft heat input.

Abstract

This invention belongs to the field of integrated thermal management research technology for aircraft and engines, and particularly relates to an experimental apparatus and method for engine thermal management considering aircraft heat input. It includes a main fuel tank, with the outlet of the main fuel tank fixedly connected to the inlet of a first filter mechanism. The outlet of the first filter mechanism is fixedly connected to the inlet of a heating heat exchange mechanism, the outlet of the heating heat exchange mechanism is fixedly connected to the inlet of a second filter mechanism, the outlet of the second filter mechanism is fixedly connected to the inlet of a cooling mechanism, and the outlet of the cooling mechanism is fixedly connected to the inlet of a return fuel tank. The outlet of the return fuel tank is fixedly connected to the inlet of the main fuel tank. This invention comprehensively considers the overall heat transfer of the aircraft and aero-engine, improving the reliability of ground experimental data for aero-engine thermal management and reducing the difficulty of ground experiments through a semi-physical experimental method.

Description

Technical Field

[0001] This invention belongs to the field of aircraft-engine integrated thermal management research technology, and particularly relates to an experimental device and method for engine thermal management that takes into account aircraft heat input. Background Technology

[0002] With the further development of advanced fighter jets, the heat generated by advanced weapons and electronic equipment on board aircraft is gradually increasing. To meet the heat dissipation requirements, the important role of fuel as a primary heat sink has become increasingly apparent. Starting with the later stages of third-generation fighter jets, fuel began to serve as the primary heat sink for cooling the aircraft and engine. Part of the fuel carried by the fighter jet is used to cool the liquid cooling system, auxiliary power system, and hydraulic system, while another part is pumped into the engine after being mixed with the fuel that has absorbed heat from various subsystems. As the combat capabilities of fighter jets further improve, fuel consumption decreases while the heat generated by airborne weapons and equipment increases. Current fuel control strategies, combined with the ever-increasing heat generation of aircraft engines, are prone to coking problems. Therefore, considering the aerodynamic heating of aircraft fuel tanks and the input of heat from fuel to various compartments, a systematic study of integrated thermal management of aircraft and engines is of great significance.

[0003] Current research on thermal management systems in the aviation field primarily focuses on aircraft engines, without fully considering the impact of aerodynamic heating of aircraft fuel tanks and the influence of multiple heat-generating components such as radar bays, avionics bays, air conditioning systems, and hydraulic systems on fuel temperature during high Mach number flights. Furthermore, because integrated aircraft-engine thermal management research involves multiple components and subsystems, conducting ground experiments directly without a real aircraft engine is extremely difficult. Current research methods mainly utilize one-dimensional commercial simulation software such as Simulink / Amesim for system construction and simulation, which involves numerous assumptions and simplifications, resulting in data that cannot directly guide engineering practice. Therefore, it is particularly important to find a reasonable simplification of the aircraft-engine thermal management system while considering the heat input during actual flight, and to obtain an integrated aircraft-engine thermal management control strategy through experimental research. Summary of the Invention

[0004] The purpose of this invention is to provide an experimental apparatus and method for engine thermal management that takes into account the heat input of the aircraft, so as to solve the above-mentioned problems, achieve comprehensive consideration of the overall heat transfer of the aircraft and the aero-engine, improve the reliability of ground experimental data on aero-engine thermal management, and reduce the difficulty of ground experiments through a semi-physical experimental method.

[0005] To achieve the above objectives, the present invention provides the following solution: an engine thermal management experimental device considering aircraft heat input, comprising a main fuel tank, wherein the outlet end of the main fuel tank is fixedly connected to the inlet end of a first filter mechanism, the outlet end of the first filter mechanism is fixedly connected to the inlet end of a heating heat exchange mechanism, the outlet end of the heating heat exchange mechanism is fixedly connected to the inlet end of a second filter mechanism, the outlet end of the second filter mechanism is fixedly connected to the inlet end of a cooling mechanism, the outlet end of the cooling mechanism is fixedly connected to the inlet end of a return fuel tank, and the outlet end of the return fuel tank is fixedly connected to the inlet end of the main fuel tank.

[0006] Preferably, the first filtration mechanism includes a pre-pump coarse filter, the inlet end of which is fixedly connected to the outlet end of the main oil tank, the outlet end of which is fixedly connected to the inlet end of a booster pump, the outlet end of which is fixedly connected to the inlet end of a post-pump fine filter, and the outlet end of which is fixedly connected to the inlet end of the heating heat exchange mechanism.

[0007] Preferably, the heating and heat exchange mechanism includes a pipeline heater, the inlet end of which is fixedly connected to the outlet end of the post-pump fine filter, the outlet end of which is fixedly connected to the inlet end of a fuel and lubricating oil heat exchanger, and the outlet end of which is fixedly connected to the inlet end of the second filtration mechanism.

[0008] Preferably, a flow meter is installed between the inlet end of the pipeline heater and the outlet end of the post-pump fine filter.

[0009] Preferably, the second filtration mechanism includes a post-processing fine filter box, the inlet end of which is fixedly connected to the outlet end of the fuel-lubricating oil heat exchanger, and the outlet end of which is fixedly connected to the inlet end of the cooling mechanism.

[0010] Preferably, the cooling mechanism includes a water cooler, the inlet end of which is fixedly connected to the outlet end of the post-operation fine filter box, and the outlet end of which is fixedly connected to the inlet end of the return oil tank.

[0011] Preferably, the main oil tank is equipped with an internal heater.

[0012] Preferably, both the main oil tank and the return oil tank are equipped with an oil drain valve and temperature and pressure measuring points.

[0013] Preferably, one-way valves are provided between the outlet end of the booster pump and the inlet end of the post-pump fine filter, and between the outlet end of the pipeline heater and the inlet end of the fuel-lubricating oil heat exchanger;

[0014] Ball valves are installed between the outlet end of the post-pump fine filter and the inlet end of the pipeline heater, between the outlet end of the post-working fine filter box and the inlet end of the water cooler, and between the outlet end of the return oil tank and the inlet end of the main oil tank.

[0015] A shut-off valve is installed between the outlet end of the pipeline heater and the inlet end of the lubricating oil heat exchanger, and between the outlet end of the lubricating oil heat exchanger and the inlet end of the post-operation fine filter box.

[0016] An experimental method for an engine thermal management experimental apparatus considering aircraft heat input includes the following steps:

[0017] S1. Remove moisture from the working oil in the main oil tank;

[0018] S2. Check the quality of the working oil in the main oil tank and heat the working oil;

[0019] S3. Turn on the booster pump to circulate the working oil, and at the same time turn on the pipeline heater and the fuel-lubricating oil heat exchanger.

[0020] S4. The experiment is repeated cyclically;

[0021] S5. After the experiment, turn off the pipeline heater and the lubricating oil heat exchanger to cool down the working oil.

[0022] Compared with the prior art, the present invention has the following advantages and technical effects:

[0023] 1. Currently, aircraft and engines are relatively independent in their development processes, but in actual application, they need to be coupled mechanically and influence each other in terms of aerodynamic heat transfer performance. This invention couples the heat generation of aircraft systems such as radar compartment, avionics compartment, air conditioning system, and hydraulic system with the heat generation of engine lubricating oil system. By controlling the on / off state of heaters and power, it performs semi-physical simulation of the temperature changes in fuel tanks within the complete flight envelope caused by flight altitude and Mach number, and the heat generation of different aircraft subsystems, to obtain an integrated flight-engine thermal management control strategy.

[0024] 2. During actual aircraft flight, the heat input to the fuel heat sink comes from multiple components. However, in ground experiments, the power required for direct heating across the entire flight envelope using a single heat source is excessive, typically reaching megawatt levels. This invention employs a multi-heat source, segmented heating method, ensuring the total heating power remains below 300 kW while simulating thermal management characteristics under different flight conditions. Compared to direct heating, the required heating power is reduced by over 70%, significantly lowering experimental costs and difficulty.

[0025] 3. This invention has rich potential for future expansion. In the experimental device, the inlet and outlet of the pipeline heater are arranged with expansion interfaces. Under the premise of further strengthening the integration of flight and engine, heat-generating components in the aircraft, such as the avionics bay, radar bay, pneumatic heating of fuel tanks at high Mach numbers, and hydraulic system heat, can be connected to this device in the form of gas-liquid heat exchangers or liquid-liquid heat exchangers. This will further increase the number of physical sub-components in this invention and make the experimental device data closer to the real situation. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the experimental apparatus of the present invention;

[0028] Figure 2 This is a flowchart of the present invention.

[0029] The components include: 1. Main oil tank; 2. In-tank heater; 3. Pre-pump coarse filter; 4. Booster pump; 5. Post-pump fine filter; 6. Flow meter; 7. Pipeline heater; 8. Fuel and lubricating oil heat exchanger; 9. Post-operation fine filter box; 10. Water cooler; 11. Return oil tank; 12. Check valve; 13. Ball valve; 14. Shut-off valve; 15. Drain valve and temperature and pressure measuring points. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] Reference Figures 1-2The present invention provides an engine thermal management experimental device considering aircraft heat input, including a main fuel tank 1, the outlet end of the main fuel tank 1 is fixedly connected to the inlet end of a first filter mechanism, the outlet end of the first filter mechanism is fixedly connected to the inlet end of a heating heat exchange mechanism, the outlet end of the heating heat exchange mechanism is fixedly connected to the inlet end of a second filter mechanism, the outlet end of the second filter mechanism is fixedly connected to the inlet end of a cooling mechanism, the outlet end of the cooling mechanism is fixedly connected to the inlet end of a return fuel tank 11, and the outlet end of the return fuel tank 11 is fixedly connected to the inlet end of the main fuel tank 1.

[0033] Aircraft fuel supply systems and engine lubrication systems are similar in basic structure; therefore, this application uses the term "working oil" for a unified description.

[0034] Main oil tank 1 provides working oil that meets the limits for water content and impurities in experimental oils, ensuring the continuous and safe operation of the experimental system.

[0035] The scheme is further optimized. The first filtration mechanism includes a pre-pump coarse filter 3. The inlet end of the pre-pump coarse filter 3 is fixedly connected to the outlet end of the main oil tank 1. The outlet end of the pre-pump coarse filter 3 is fixedly connected to the inlet end of the booster pump 4. The outlet end of the booster pump 4 is fixedly connected to the inlet end of the post-pump fine filter 5. The outlet end of the post-pump fine filter 5 is fixedly connected to the inlet end of the heating heat exchange mechanism.

[0036] The pre-pump coarse filter 3 performs preliminary filtration of the working oil during the experimental cycle. The filtration accuracy is 30μm. The main objects filtered are metal shavings generated during the experiment and a small amount of coking products caused by the increase in the temperature of the working oil, thereby improving the safety margin of the experimental device.

[0037] The booster pump 4 increases the working oil pressure, which, for the fuel system, simulates the fuel working pressure under real engine conditions and meets the simulation standards of the experimental system.

[0038] The post-pump fine filter 5 performs secondary filtration on the high-pressure working oil after the booster pump 4. The filtration accuracy is 5μm. The main target of filtration is the impurities remaining in the oil after the initial filtration, ensuring that the quality of the working oil before entering the lubricating oil heat exchanger 8 meets the standards.

[0039] The scheme is further optimized. The heating and heat exchange mechanism includes a pipeline heater 7. The inlet end of the pipeline heater 7 is fixedly connected to the outlet end of the post-pump fine filter 5. The outlet end of the pipeline heater 7 is fixedly connected to the inlet end of the fuel lubricating oil heat exchanger 8. The outlet end of the fuel lubricating oil heat exchanger 8 is fixedly connected to the inlet end of the second filtration mechanism.

[0040] The pipeline heater 7 provides instantaneous heat input to the working oil, mainly simulating the heat input from the radar compartment, electronics compartment, cockpit, and other compartments during actual aircraft flight, as well as the heat input generated by the hydraulic system during operation. The pipeline heater 7 works in conjunction with the in-tank heater 2 and the water cooler 10 to ensure that the oil temperature meets the requirements of the experimental setup.

[0041] The main function of the fuel-oil heat exchanger is to provide a place for heat exchange between fuel oil and lubricating oil. This heat exchanger uses a shell-and-tube radiator. The hot fluid lubricating oil flows through the shell side, and the cold fluid fuel oil flows through the tube side. After completing the heat exchange process, they flow out of the heat exchanger respectively.

[0042] To further optimize the design, a flow meter 6 is installed between the inlet end of the pipeline heater 7 and the outlet end of the post-pump fine filter 5.

[0043] Flowmeter 6 detects the flow rate of the working oil in the flow path and matches it with the oil flow rate required for the experimental process.

[0044] The scheme is further optimized. The second filtration mechanism includes a post-working fine filter box 9. The inlet end of the post-working fine filter box 9 is fixedly connected to the outlet end of the fuel-lubricating oil heat exchanger 8, and the outlet end of the post-working fine filter box 9 is fixedly connected to the inlet end of the cooling mechanism.

[0045] The post-work fine filter box 9 filters the oil after work with a filtration accuracy of 5μm. The purpose is to filter out coking products or particulate matter that settle due to the rise or fall of the working oil temperature, reduce the impurity content of the return oil, and improve the cleanliness of the oil.

[0046] The scheme is further optimized. The cooling mechanism includes a water cooler 10. The inlet end of the water cooler 10 is fixedly connected to the outlet end of the fine filter box 9 after operation, and the outlet end of the water cooler 10 is fixedly connected to the inlet end of the return oil tank 11.

[0047] The water cooler 10 reduces the return temperature of the working oil, simulating the operation of a real aircraft engine. The air-fuel lubricating oil heat exchanger 8 provides secondary cooling of the working oil, improving the heat sink's working capacity.

[0048] To further optimize the design, an internal heater 2 is installed inside the main oil tank 1.

[0049] The in-tank heater 2 provides some heat input to the working oil in the main oil tank 1, and together with the pipeline heater 7 and water cooler 10, controls the input temperature of the working oil to ensure that the working oil temperature meets the requirements during the experiment.

[0050] The design has been further optimized by installing an oil drain valve and temperature and pressure measuring points 15 on both the main oil tank 1 and the return oil tank 11.

[0051] The return fuel tank 11 provides storage space for the oil after operation. The purpose of the return fuel tank 11 is to simulate the process of fuel cooling the lubricating oil before entering the combustion chamber for consumption when a real aircraft engine is working. At the same time, it is connected to the main fuel tank 1 to complete the overall architecture of the circulation system and provide operating space for supporting systems such as water removal equipment and oil cleanliness testing equipment.

[0052] To further optimize the scheme, one-way valves 12 are installed between the outlet end of booster pump 4 and the inlet end of post-pump fine filter 5, and between the outlet end of pipeline heater 7 and the inlet end of fuel lubricating oil heat exchanger 8.

[0053] Ball valves 13 are installed between the outlet end of the post-pump fine filter 5 and the inlet end of the pipeline heater 7, between the outlet end of the post-operation fine filter box 9 and the inlet end of the water cooler 10, and between the outlet end of the return oil tank 11 and the inlet end of the main oil tank 1.

[0054] A shut-off valve 14 is installed between the outlet end of the pipeline heater 7 and the inlet end of the fuel oil heat exchanger 8, and between the outlet end of the fuel oil heat exchanger 8 and the inlet end of the post-operation fine filter box 9.

[0055] The main function of the one-way valve 12 is to ensure the one-way circulation and prevent the hot fuel after heating from mixing with the cold fuel after unheating, which would increase the risk and difficulty of the experiment. The main function of the ball valve 13 is to regulate the flow rate of the working oil in real time so that the regulation parameters match the actual working conditions of the aero-engine. The main function of the shut-off valve 14 is to control the opening and closing of the circulation path and also serves as a safety valve to ensure the reliability and safety of the experimental system. The drain valve and the drain valve in the temperature and pressure measuring point 15 are accessories of the main oil tank 1 and the return oil tank 11. Their main function is to facilitate the recovery and storage of the working oil after the experiment.

[0056] An experimental method for an engine thermal management experimental apparatus considering aircraft heat input includes the following steps:

[0057] S1. Remove moisture from the working oil in the main oil tank 1;

[0058] Before the experiment begins, the water removal system of the main oil tank 1 is turned on and the moisture content of the working oil in the main oil tank 1 is monitored in real time. It should be noted that the water removal system of the main oil tank 1 is an experimental support system and an accessory of the experimental device involved in this invention. The composition and principle of the water removal system are not discussed in this invention. When the moisture sensor detects that the moisture content of the oil meets the experimental requirements, it sends a response signal. At this time, the water removal system is turned off and does not work simultaneously with the integrated thermal management semi-physical experimental device of the aircraft and engine involved in this invention.

[0059] S2. Check the quality of the working oil in the main oil tank 1 and heat the working oil;

[0060] S3. Start the booster pump 4 to circulate the working oil, and at the same time start the pipeline heater 7 and the lubricating oil heat exchanger 8.

[0061] The working oil detection sensor is activated to detect impurities such as metal shavings and coking products in the fuel or lubricating oil in real time during the experiment. The lubricating oil tank heater is turned on to gradually increase the temperature of the lubricating oil in the tank and maintain it at 100°C. When the oil tank temperature sensor detects that the lubricating oil temperature has stabilized, the booster pump 4 is turned on to control the lubricating oil pipeline heater 7 to start working. Heat is input into the lubricating oil through the pipeline heater 7, and at the same time, it works with the water cooler 10 to regulate and control the lubricating oil temperature, simulating the heat generation of bearings and accessories under different engine operating conditions. The purpose of using the pipeline heater 7 is to improve the experimental device's ability to control the lubricating oil temperature and shorten the heating time. At the same time, the fuel pump is turned on to pump hot-sinking fuel into the fuel-lubricating oil heater. The fuel is not heated at the beginning of the experiment to simulate the cooling characteristics of the fuel on the lubricating oil under ground slow conditions.

[0062] S4. The experiment is repeated cyclically. Hot lubricating oil continuously inputs heat to cold fuel. The fuel tank heater and fuel pipeline heater 7 are turned on to input heat to the fuel. The return oil temperature is adjusted by controlling the water cooler 10, and the fuel temperature in the main fuel tank 1 is controlled to change from 20℃ to 70℃, simulating the cooling characteristics of fuel on lubricating oil under aircraft cruise conditions. As hot lubricating oil continuously inputs heat to cold fuel, the initial temperature of the fuel gradually increases when it flows through the pipeline heater 7. Under the premise of the same target temperature, the power of the pipeline heater 7 can be continuously reduced. When the output power of the fuel pipeline heater 7 is 0, the temperature in the fuel tank is maintained at 70℃ by the fuel tank heater and water cooler 10. The pipeline heater 7 is turned on again to input heat to the fuel, and the output fuel temperature is adjusted to a range of 70-120℃, simulating the cooling characteristics of fuel on lubricating oil when the aircraft is subjected to instantaneous heat load. The experimental data acquisition system records the temperature-pressure-flow characteristic data of the fuel lubricating oil in real time, and optimizes the current thermal management system control strategy through data analysis.

[0063] S5. After the experiment, turn off the pipeline heater 7 and the lubricating oil heat exchanger 8 to cool down the working oil.

[0064] After the experiment is completed, all heating equipment in the experimental apparatus is turned off, and the temperature of the working oil is reduced to the initial state by water cooler 10, thus ending the experiment. After the phased experiment is completed, the working oil in the experimental apparatus is drained through the drain valve and stored separately.

[0065] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0066] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. An experimental apparatus for engine thermal management considering aircraft heat input, characterized in that, Includes a main oil tank (1), an in-tank heater (2) is provided inside the main oil tank (1), the outlet end of the main oil tank (1) is fixedly connected to the inlet end of a first filter mechanism, the outlet end of the first filter mechanism is fixedly connected to the inlet end of a heating heat exchange mechanism, the outlet end of the heating heat exchange mechanism is fixedly connected to the inlet end of a second filter mechanism, the outlet end of the second filter mechanism is fixedly connected to the inlet end of a cooling mechanism, the outlet end of the cooling mechanism is fixedly connected to the inlet end of a return oil tank (11), and the outlet end of the return oil tank (11) is fixedly connected to the inlet end of the main oil tank (1). The first filtration mechanism includes a pre-pump coarse filter (3), the inlet end of which is fixedly connected to the outlet end of the main oil tank (1), the outlet end of which is fixedly connected to the inlet end of a booster pump (4), the outlet end of which is fixedly connected to the inlet end of a post-pump fine filter (5), and the outlet end of which is fixedly connected to the inlet end of the heating heat exchange mechanism. The heating and heat exchange mechanism includes a pipe heater (7), the inlet end of which is fixedly connected to the outlet end of the post-pump fine filter (5), the outlet end of which is fixedly connected to the inlet end of a fuel oil heat exchanger (8), and the outlet end of the fuel oil heat exchanger (8) is fixedly connected to the inlet end of the second filter mechanism.

2. The engine thermal management experimental apparatus considering aircraft heat input according to claim 1, characterized in that, A flow meter (6) is installed between the inlet end of the pipeline heater (7) and the outlet end of the post-pump fine filter (5).

3. The engine thermal management experimental apparatus considering aircraft heat input according to claim 2, characterized in that, The second filtration mechanism includes a post-working fine filter box (9), the inlet end of which is fixedly connected to the outlet end of the fuel-lubricating oil heat exchanger (8), and the outlet end of which is fixedly connected to the inlet end of the cooling mechanism.

4. The engine thermal management experimental apparatus considering aircraft heat input according to claim 3, characterized in that, The cooling mechanism includes a water cooler (10), the inlet end of which is fixedly connected to the outlet end of the working fine filter box (9), and the outlet end of which is fixedly connected to the inlet end of the return oil tank (11).

5. An engine thermal management experimental apparatus considering aircraft heat input according to claim 1, characterized in that, Both the main oil tank (1) and the return oil tank (11) are equipped with an oil drain valve and temperature and pressure measuring points (15).

6. An engine thermal management experimental apparatus considering aircraft heat input according to claim 4, characterized in that, One-way valves (12) are provided between the outlet end of the booster pump (4) and the inlet end of the post-pump fine filter (5), and between the outlet end of the pipeline heater (7) and the inlet end of the fuel oil heat exchanger (8); Ball valves (13) are provided between the outlet end of the post-pump fine filter (5) and the inlet end of the pipeline heater (7), between the outlet end of the post-working fine filter box (9) and the inlet end of the water cooler (10), and between the outlet end of the return oil tank (11) and the inlet end of the main oil tank (1). A shut-off valve (14) is provided between the outlet end of the pipeline heater (7) and the inlet end of the lubricating oil heat exchanger (8), and between the outlet end of the lubricating oil heat exchanger (8) and the inlet end of the post-operation fine filter box (9).

7. An experimental method for an engine thermal management experimental apparatus considering aircraft heat input, as described in any one of claims 1-6, characterized in that, Includes the following steps: S1. Remove water from the working oil in the main oil tank (1); S2. Check the quality of the working oil in the main oil tank (1) and heat the working oil. S3. Turn on the booster pump (4) to circulate the working oil, and at the same time turn on the pipeline heater (7) and the lubricating oil heat exchanger (8); S4. The experiment is repeated cyclically; S5. After the experiment, turn off the pipeline heater (7) and the lubricating oil heat exchanger (8) to cool down the working oil.

Images