A test cabin engine combined debugging method based on an auxiliary power device

Abstract

This invention belongs to the field of high-altitude simulation testing technology for aero-engines, and provides a method for joint engine commissioning within a test chamber based on the auxiliary power unit (APU). The method involves configuring a dedicated air supply pipeline for the APU, independent of the main engine air supply system, within a single, sealed test chamber. This pipeline is equipped with an APU air supply regulating valve, an air supply venting valve, and an intake environment parameter measurement system. An openable and closable thermal insulation cover is installed around this pipeline, forming a sub-simulation environment that is physically isolated from the main environment, thermally decoupled, and has independently controllable parameters. The method includes: performing multi-mode joint purging of the dedicated air supply pipeline; constructing a mapping control model between the APU air supply regulating system and environmental conditions; performing joint ground commissioning of the APU and engine; and performing in-flight start-up and joint operation commissioning of the engine. This invention solves the technical challenge of simultaneously simulating both the main and sub-engine high-altitude environments within a single test chamber, improving the fidelity of joint commissioning and flight test safety.

Description

Technical Field

[0001] This invention belongs to the field of high-altitude simulation test technology for aero-engines, and relates to a method for joint debugging of the main engine and auxiliary power unit (APU) in a single closed high-altitude simulation test chamber, which is particularly suitable for ground condition verification and collaborative function testing under high-altitude flight conditions. Background Technology

[0002] Before conducting joint commissioning tests of the auxiliary power unit and the aero-engine, the air supply system must be fully prepared. However, the existing test procedures lack standardized cleaning and purging methods for the dedicated air supply pipelines of the auxiliary power unit. Residual particulate matter, welding slag, or moisture in the pipelines can easily cause valve jamming, flow drift, or even start-up failure. At the same time, the commissioning of the air supply system relies heavily on experience-based adjustments, and a quantitative control model has not been established between the opening of the auxiliary power unit's intake regulating valve and the total intake pressure, ambient pressure, and air flow rate under high-altitude conditions, making it difficult to guarantee simulation accuracy and repeatability.

[0003] During the ground-based joint commissioning phase, if the auxiliary power unit is operated within a high-altitude simulation test chamber equipped with an insulation cover, the exhaust cannot effectively diffuse due to the completely closed insulation cover. This can easily lead to localized heat accumulation and increased back pressure, severely affecting the stable operation of the auxiliary power unit. Furthermore, existing test procedures do not clearly specify the opening and closing status of the insulation cover during ground commissioning, nor do they provide feasible structural operation guidelines, resulting in frequent interruptions to ground-based joint commissioning due to poor exhaust.

[0004] More importantly, in terms of joint commissioning under simulated in-flight conditions, existing high-altitude simulation test chambers can only construct a single, uniform cabin environment, and cannot create localized high-altitude operating conditions for the auxiliary power unit that match its actual flight position. Since the pressure and temperature environments of the auxiliary power unit and the engine are the same in actual flight, existing equipment cannot simulate the inlet environmental conditions of the auxiliary power unit, which makes its in-flight operation prone to distortion and cannot verify the true collaborative capabilities of the two under typical mission profiles (such as in-flight restart and high-altitude start-up).

[0005] Furthermore, there is currently no effective technical means to simultaneously construct two independent and controllable sub-environments within a single test chamber, which severely restricts the conduct of high-fidelity joint debugging tests and increases the technical risks of subsequent flight tests. Summary of the Invention

[0006] In order to solve the technical problem that existing technologies cannot perform differentiated environmental simulation and full-process joint debugging of engines and auxiliary power units in the same high-altitude simulation test chamber, and to achieve the purpose of improving test fidelity and reducing flight test risks, this invention discloses a joint debugging method for engines in a test chamber based on auxiliary power units.

[0007] The test chamber is a sealed structure equipped with an atmospheric intake valve, a direct atmospheric exhaust valve, an engine intake regulating valve, and a chamber temperature control regulating valve, and houses an engine and an auxiliary power unit. A dedicated air supply pipeline, independent of the engine's main air supply system, is provided for the auxiliary power unit. This dedicated pipeline includes an auxiliary power unit air supply regulating valve, an auxiliary power unit air supply vent valve, and an intake environment parameter measurement system. An openable and closable thermal insulation cover is installed around this pipeline to create a sub-simulated environment within the test chamber that is physically isolated from, thermally decoupled from, the main environment of the engine, and whose environmental parameters are independently controllable.

[0008] The method includes the following steps in sequence: S1. Perform multi-mode combined purging on the dedicated gas supply pipeline; S2. Construct a mapping control model between the opening degree of the auxiliary power unit's air supply regulating valve and the total intake pressure, ambient pressure, and air flow rate. S3. Conduct joint ground testing of the auxiliary power unit and the engine; S4. Perform in-flight start-up and joint operation testing on the engine.

[0009] Further, in step S1, air is supplied by the ambient temperature air supply valve. Under the condition that the negative temperature air supply valve, the high temperature air supply valve, the engine intake air regulating valve and the cabin temperature control regulating valve are closed, steady-state purging, pulsating disturbance purging and high-pressure venting are carried out in sequence by controlling the auxiliary power unit air supply regulating valve and the auxiliary power unit air supply venting valve.

[0010] Furthermore, in step S1, the multi-mode joint purging includes: S11. Close the auxiliary power unit air supply vent valve, slowly open the auxiliary power unit air supply regulating valve, and use a clean air source with a pressure not lower than the actual maximum working pressure to perform steady-state purging on the dedicated air supply pipeline for a duration of not less than 3 minutes. S12. Maintain stable air supply pressure, control the auxiliary power unit air supply regulating valve to reciprocate within the 20% to 80% opening range with a preset minimum action cycle to generate pressure pulsation to remove impurities attached to the dedicated air supply pipeline, realize pulsating disturbance purging, and the duration is not less than 1 minute. S13. Simultaneously fully open the auxiliary power unit air supply vent valve and increase the opening of the auxiliary power unit air supply regulating valve to not less than 50%. Through high-speed airflow, the residual pollutants in the dedicated air supply pipeline are discharged through the auxiliary power unit air supply vent valve to the common exhaust channel or dedicated collection system in the test chamber, realizing high-pressure venting and purging, with a duration of not less than 3 minutes.

[0011] Further, in step S2, based on the dedicated air supply pipeline after purging, the auxiliary power unit air supply regulating valve and the optional main environmental control valve are adjusted under different simulated high-altitude operating conditions to make the measured air flow rate approach the theoretical requirement value. After each operating condition stabilizes, the corresponding valve opening, total intake pressure, environmental pressure, and flow rate data are recorded. Based on the recorded data, a mapping control model of the auxiliary power unit air supply regulating valve opening with respect to total intake pressure, environmental pressure, and air flow rate is constructed using multinomial regression or neural network methods.

[0012] Furthermore, in step S3, with the insulation cover in a non-closed state and the atmospheric intake valve and the direct exhaust valve fully open, the auxiliary power unit and the engine are jointly debugged on the ground.

[0013] Furthermore, the statement that the insulation cover is in a non-closed state means that one side of its shell is removed, or that a ventilation gap is maintained between the left and right shells to ensure that the exhaust gas from the auxiliary power unit can diffuse freely.

[0014] Furthermore, in step S4, under the condition that the heat insulation cover is closed and the atmospheric intake valve and the direct exhaust atmospheric valve are closed, the main environmental parameters of the engine and the sub-environmental parameters of the auxiliary power unit are adjusted independently and separately according to the mapping control model. The main environmental parameters are achieved by regulating the engine intake regulating valve and the cabin temperature control regulating valve; the sub-environmental parameters are achieved by regulating the auxiliary power unit air supply regulating valve and the auxiliary power unit air supply venting valve; thereby constructing a parallel simulation state of the main and sub-environments that meets the conditions for high-altitude flight, and performing engine in-flight start-up and joint operation debugging in this state.

[0015] Furthermore, the test chamber is also equipped with a high-temperature gas supply valve, a normal-temperature gas supply valve, and a negative-temperature gas supply valve to provide gas sources of different temperature levels to the main environment; the adjustment of the main environment parameters also includes regulating one or more of the high-temperature gas supply valve, the normal-temperature gas supply valve, and the negative-temperature gas supply valve.

[0016] In an improved embodiment of the above-described method for joint engine commissioning in the test chamber based on an auxiliary power unit, the method further includes: S5. After the joint commissioning test is completed, adjust the auxiliary power unit air supply regulating valve to a preset non-zero opening degree, and use the continuous clean airflow from the dedicated air supply pipeline to force-cool the turbine and exhaust section hot end components of the auxiliary power unit until its exhaust temperature drops below the safety threshold, and then close the auxiliary power unit air supply regulating valve and the auxiliary power unit air supply vent valve.

[0017] Furthermore, the sub-simulated environment formed in the test chamber can be set to operating conditions that are significantly different from or the same as the main environment, so that the auxiliary power unit and the engine can operate simultaneously under the same or different typical high-altitude conditions, in order to verify their collaborative working ability in real flight.

[0018] The method of the present invention is an integrated joint commissioning method. It constructs a physically isolated master-slave dual environment with independent parameters in a single sealed test chamber, realizing synchronous commissioning of the engine and APU under their respective typical high-altitude operating conditions, thereby improving test fidelity and system reliability.

[0019] Compared with traditional experimental methods, the method of the present invention has at least the following advantages: 1. Traditional commissioning methods for the preparation of air supply systems often rely on experience-based adjustments, lacking systematic guarantees for pipeline cleanliness and control accuracy. This invention employs a three-stage combined purging process—steady-state, pulsating, and venting—to thoroughly remove particulate matter and moisture. Furthermore, based on multi-condition calibration, a quantitative control model is established between the engine intake regulating valve opening and the total intake pressure, ambient pressure, and airflow. This forms a repeatable and highly accurate air supply commissioning and calibration system, significantly improving the reliability and consistency of high-altitude simulation.

[0020] 2. Traditional solutions for ground-based joint commissioning do not consider the impact of the insulation cover on the exhaust of the auxiliary power unit, often leading to operational abnormalities due to increased back pressure or heat accumulation. This invention specifies that during ground commissioning, one side of the insulation cover should be removed or the left and right sides should remain open to create an effective ventilation gap, ensuring free diffusion of exhaust. This operational procedure fundamentally solves the problem of poor exhaust during ground testing with the cover on, ensuring the smooth implementation of ground functional verification.

[0021] 3. Regarding high-altitude joint testing capabilities, traditional high-altitude simulation test chambers can only provide a single, uniform environment, failing to replicate the aerial conditions encountered by the auxiliary power unit and engine during actual flight, leading to distortion in joint testing. This invention, by independently controlling the main environment (managed by engine intake / cabin temperature / pressure valves) and the sub-environment (managed by APU-dedicated air supply / venting valves), achieves, for the first time, parallel simulation of dual high-altitude operating conditions within a single chamber. This successfully supports ground verification of key scenarios such as in-flight restart and high-altitude start-up, significantly reducing flight test risks and substantially expanding the capabilities of high-altitude simulation testing. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a layout diagram of the test chamber; Figure 2 This is a schematic diagram of the air supply principle inside the test chamber; Figure 3 Diagram showing the installation and flow measurement of the auxiliary power unit's air supply device.

[0024] Figure 4 This is a flowchart of the joint commissioning method for engines in the test chamber based on auxiliary power units; The components include: 1. Test chamber; 2. Engine; 3. Auxiliary power unit; 4. Insulation cover; 911. Atmospheric intake valve; 912. Direct atmospheric exhaust valve; 101. Normal temperature air supply valve; 102. Negative temperature air supply valve; 103. High temperature air supply valve; 111. Engine intake regulating valve; 112. Chamber temperature control regulating valve; 113. Auxiliary power unit air supply regulating valve; 114. Auxiliary power unit air supply vent valve; and 115. Ambient pressure regulating valve. Detailed Implementation

[0025] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0026] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. This application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, in the absence of conflict, the following embodiments and features of the embodiments can be combined with each other. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0027] This invention discloses a method for joint commissioning of an engine in a test chamber based on an auxiliary power unit. Taking the commissioning test of an auxiliary power unit of a certain type of engine in a test chamber as an example, the method adopts a progressive step of "first single system calibration, then dual system joint commissioning" to complete pipeline cleaning and purging, air supply system commissioning, and ground and high-altitude joint commissioning in sequence.

[0028] like Figures 1 to 3 As shown, Figure 1The image shows the engine 2, auxiliary power unit 3 and their relative positions to the supply and exhaust valve system. The test chamber 1 is a sealed structure, equipped with an atmospheric intake valve 911, a direct exhaust atmospheric valve 912, an engine intake regulating valve 111 and a chamber temperature control regulating valve 112, and is equipped with the engine 2 and auxiliary power unit 3.

[0029] This invention provides the auxiliary power unit 3 with a dedicated air supply pipeline independent of the main air supply system of the engine 2. This dedicated air supply pipeline is equipped with an auxiliary power unit air supply regulating valve 113, an auxiliary power unit air supply vent valve 114, and an intake air environment parameter measurement system. An openable and closable thermal insulation cover 4 is installed around it to create a sub-simulation environment within the test chamber 1 that is physically isolated from, thermally decoupled from, the main environment of the engine 2, and whose environmental parameters are independently controllable.

[0030] Among them, the high-temperature air supply valve 103, the normal-temperature air supply valve 101 and the negative-temperature air supply valve 102 are combined to regulate the intake air temperature; the engine intake air regulating valve 111 regulates the engine inlet pressure; the auxiliary power unit air supply regulating valve 113 and the auxiliary power unit air supply vent valve 114 are combined to regulate the auxiliary power unit intake pressure; the cabin temperature control regulating valve 112 controls the cabin temperature by controlling the secondary flow rate in the cabin; and the environmental pressure regulating valve 115 controls the environmental pressure in the test cabin.

[0031] The test equipment includes mechanical devices, a testing system, and an electrical control system. After the systems are installed, static debugging and inspection are conducted. Only after the debugging and inspection are completed without any abnormalities can clean purging and air supply debugging proceed. After the debugging and testing are completed, tests under ground conditions and simulated high-altitude conditions are carried out according to the test requirements. For details, see [link to relevant documentation]. Figure 4 As shown, the method includes the following steps in sequence: S1. Perform multi-mode combined purging on the dedicated gas supply pipeline; S2. Construct a mapping control model between the opening degree of the auxiliary power unit air supply regulating valve 113 of the auxiliary power unit 3 and the total intake pressure, ambient pressure and air flow rate. S3. Conduct joint ground testing of the auxiliary power unit 3 and the engine 2; S4. Perform in-flight start-up and joint operation testing on the engine 2.

[0032] Further, in step S1, air is supplied by the ambient temperature air supply valve 101. Under the condition that the negative temperature air supply valve 102, the high temperature air supply valve 103, the engine intake air regulating valve 111 and the cabin temperature control regulating valve 112 are closed, steady-state purging, pulsating disturbance purging and high-pressure venting are carried out in sequence by controlling the auxiliary power unit air supply regulating valve 113 and the auxiliary power unit air supply venting valve 114.

[0033] Furthermore, in step S1, the multi-mode joint purging includes: S11. Close the auxiliary power unit air supply vent valve 114, slowly open the auxiliary power unit air supply regulating valve 113, and use a clean air source with a pressure not lower than the actual maximum working pressure to perform steady-state purging on the dedicated air supply pipeline for a duration of not less than 3 minutes. S12. Maintain stable air supply pressure, control the auxiliary power device air supply regulating valve 113 to reciprocate within the opening range of 20% to 80% with a preset minimum operating cycle to generate pressure pulsation to remove impurities attached to the dedicated air supply pipeline, realize pulsating disturbance purging, and the duration is not less than 1 minute. S13. Simultaneously fully open the auxiliary power unit air supply vent valve 114 and increase the opening degree of the auxiliary power unit air supply regulating valve 113 to not less than 50%. Through high-speed airflow, the residual pollutants in the dedicated air supply pipeline are discharged through the auxiliary power unit air supply vent valve 114 to the common exhaust channel or dedicated collection system in the test chamber 1 to achieve high-pressure venting and purging, with a duration of not less than 3 minutes.

[0034] Further, in step S2, based on the dedicated air supply pipeline after purging, the auxiliary power unit air supply regulating valve 113 and the optional main environmental control valve are adjusted under different simulated high-altitude working conditions to make the measured air flow rate approach the theoretical requirement value. After each working condition stabilizes, the corresponding valve opening, total intake pressure, environmental pressure, and flow rate data are recorded. Based on the recorded data, a mapping control model of the opening of the auxiliary power unit air supply regulating valve 113 with respect to the total intake pressure, environmental pressure, and air flow rate is constructed using multinomial regression or neural network methods.

[0035] Furthermore, in step S3, under the condition that the heat insulation cover 4 is in a non-closed state and the atmospheric intake valve 911 and the direct exhaust atmospheric valve 912 are fully open, the ground joint commissioning of the auxiliary power unit 3 and the engine 2 is carried out.

[0036] Furthermore, the fact that the heat insulation cover 4 is in a non-closed state means that one side of its shell is removed, or that a ventilation gap is maintained between the left and right shells to ensure that the exhaust of the auxiliary power unit 3 can diffuse freely.

[0037] Further, in step S4, under the condition that the heat insulation cover 4 is closed and the atmospheric intake valve 911 and the direct exhaust atmospheric valve 912 are closed, the main environmental parameters of the engine 2 and the sub-environmental parameters of the auxiliary power unit 3 are adjusted independently and separately according to the mapping control model. The main environmental parameters are achieved by regulating the engine intake regulating valve 111 and the cabin temperature control regulating valve 112; the sub-environmental parameters are achieved by regulating the auxiliary power unit air supply regulating valve 113 and the auxiliary power unit air supply venting valve 114; thereby constructing a parallel simulation state of the main-sub dual environment that meets the conditions for high-altitude flight, and performing in-flight start-up and joint operation debugging of engine 2 in this state.

[0038] Furthermore, the test chamber 1 is also equipped with a high-temperature gas supply valve 103, a normal-temperature gas supply valve 101, and a negative-temperature gas supply valve 102, which are used to provide gas sources of different temperature levels to the main environment; the adjustment of the main environment parameters also includes regulating one or more of the high-temperature gas supply valve 103, the normal-temperature gas supply valve 101, and the negative-temperature gas supply valve 102.

[0039] In an improved embodiment of the above-described method for joint engine commissioning in the test chamber based on an auxiliary power unit, the method further includes: S5. After the joint commissioning test is completed, adjust the auxiliary power unit air supply regulating valve 113 to a preset non-zero opening degree, and use the continuous clean airflow from the dedicated air supply pipeline to force-cool the turbine and exhaust section hot end components of the auxiliary power unit 3 until its exhaust temperature drops below the safety threshold, and then close the auxiliary power unit air supply regulating valve 113 and the auxiliary power unit air supply vent valve 114.

[0040] Furthermore, the sub-simulated environment formed in the test chamber 1 can be set to operating conditions that are significantly different from or the same as the main environment, so that the auxiliary power unit 3 and the engine 2 can operate simultaneously under the same or different typical high-altitude conditions, in order to verify their cross-airspace collaborative working capability in real flight.

[0041] This invention illustrates the above method by taking the joint commissioning of a certain type of engine and auxiliary power unit in a test chamber as an example: Step 1: Before installing the insulation cover 4 and auxiliary power unit 3, clean and purge the gas supply system pipelines according to step S1.

[0042] Step 1.1: Distribute multiple total temperature and total pressure measuring rakes (each rake has multiple measuring points) and multiple wall static pressure measuring points evenly around the circumference of the flow parameter measurement section to measure the intake total temperature of the auxiliary power unit during the test. Total intake pressure Inlet wall static pressure, total intake pressure ; Step 1.2: Gas is supplied by the gas supply system, when Adjust the opening of the auxiliary power unit air supply regulating valve 113 when the ascent begins to ensure... <P tsmax (Maximum allowable pressure during design), if necessary, the auxiliary power unit air supply vent valve 114 can be adjusted to ensure that the air supply pressure does not exceed the limit value, and the auxiliary power unit air supply regulating valve 113 is opened to no less than 80%; Step 1.3: When Start timing when the maximum allowable pressure is reached, with a purging time of at least 3 minutes, and record the valve opening. Step 1.4: Keep the opening of the auxiliary power unit air supply vent valve 114 unchanged, adjust the opening of the auxiliary power unit air supply regulating valve 113 to 30% within the shortest time allowed by the valve, and adjust the opening of the auxiliary power unit air supply regulating valve 113 to 80% after the valve position is stable. Step 1.5: Repeat step 1.4 for at least 1 minute to perform oscillatory purging of the pipeline; Step 1.6: Gas supply system shut down, wait... After restoring to ambient pressure, check the gas supply lines and valves. If there are no abnormalities, the purging is complete. Step 1.7: If there are foreign objects such as sand or welding slag in the pipeline or valve, repeat steps 1.2 to 1.6 until the pipeline is clean and free of foreign objects.

[0043] After completing step 1, proceed to step 2, which involves debugging the gas supply system. Step 2.1: According to the formula ,in This represents the average value of the measured total inlet pressure. Step 2.2: According to the formula ,in This represents the average measured total inlet temperature. Step 2.3: According to the formula ,in This represents the average measured static pressure at the inlet wall. Step 2.4: According to the formula Calculate the physical airflow rate (kg / s), of which , , In the formula, A (㎡) is the cross-sectional area for flow measurement, R is the gas constant (value is 287.0), k is a coefficient (value is 1.4), and C is the drag coefficient. The velocity coefficient; Step 2.5: According to the formula Calculate the physical airflow of the auxiliary power unit (kg / s) This is the correction factor for the flow measurement pipeline; Step 2.6: Based on the constructed mapping control model, adjust the environmental pressure regulating valve 115 so that P sch ≈P sch,1 Adjusting the auxiliary power unit air supply regulating valve 113 Make ≈ ,in The airflow rate for the auxiliary power unit to achieve the minimum stable operating condition under this environmental pressure. Step 2.7: During the flow rate adjustment process, the auxiliary power unit's air vent valve 114 can be used for auxiliary adjustment; Step 2.8: Adjust by regulating the auxiliary power unit air supply regulating valve 113 Make ≈ , The airflow that assists the power unit in achieving maximum stable operation under this environmental pressure condition; Step 2.9: When Timing begins when the set value is reached and the parameters are basically stable. After 2 minutes of stability, the steady-state parameters are recorded. Step 2.10: Adjust the ambient pressure regulating valve 115 to make P sch ≈P sch,2 Repeat steps 2.6 to 2.9 for testing and debugging until all test data are obtained; Step 2.11: Based on the obtained , P sch , In addition to valve opening data, the relationship between the above data is obtained through mathematical modeling.

[0044] After completing step 2, install the auxiliary power unit and related pipelines according to the installation requirements, and complete the installation of the insulation cover (the insulation cover shell should not be closed or the left side should not be installed). Conduct ground-based commissioning tests according to step 3 below, specifically including the following processes: Step 3.1: Before the test, the atmospheric intake valve 911, the direct exhaust atmospheric valve 912, the engine intake regulating valve 111, and the cabin temperature control regulating valve 112 are fully open; Step 3.2: Auxiliary power unit unsealing and commissioning. Unseal the auxiliary power unit according to the unsealing procedure. During the unsealing process, pay close attention to parameters such as lubricating oil pressure, speed, fuel injection timing, and fuel injection flow rate. After the test, check and remove the fuel around the engine. Step 3.3: Cold-state operation and commissioning of auxiliary power unit. Conduct cold-state operation test of auxiliary power unit according to cold-state operation procedure. During cold-state operation, pay close attention to parameters such as lubricating oil pressure and speed. After the test, check and remove any fuel accumulated in the engine flow passage and exhaust flow passage. Step 3.4: Start-up and commissioning of auxiliary power unit. Start the auxiliary power unit according to the procedure until it reaches the minimum stable operating state, and maintain stable operation for no less than 30 seconds; Step 3.5: Debugging the auxiliary power unit to its maximum stable operating state. Adjust the auxiliary power unit to its maximum stable operating state and maintain stable operation for at least 10 seconds; Step 3.6: Engine Unsealing and Testing. Unseal the engine according to the engine unsealing procedure, monitor the parameters, and check the results after the test to ensure consistency with Step 3.1. Check the engine lubricating oil level. Step 3.7: Auxiliary power unit shutdown and commissioning. If the lubricating oil level is lower than the limit value in Step 3.5, the auxiliary power unit shall be reduced to the minimum stable operating state for 30 seconds and then stopped; after adding engine lubricating oil to the specified level, the auxiliary power unit shall be started and run to the maximum stable operating state according to the procedure of Steps 3.3 to 3.5. Step 3.8: If no additional lubricating oil is needed, proceed directly to the test procedure in step 3.9; Step 3.9: Engine cold run test. Perform the engine cold run test according to the cold run procedure. After the cold run is completed, the auxiliary power unit shall be stopped according to the procedure in Step 3.6. The monitored parameters and inspection items are the same as in Step 3.2. Step 3.10: Engine Start-up and Testing. Start the auxiliary power unit according to the procedures in Steps 3.1 to 3.5 and run it to the maximum stable operating state. Start the engine to idle and check the joint operation of the auxiliary power unit and the engine under ground conditions. During the start-up process, monitor parameters such as the auxiliary power unit speed, exhaust temperature, and bleed air pressure, as well as parameters such as engine speed, fuel supply flow rate, engine exhaust temperature, starter disengagement speed, and lubricating oil pressure. Step 3.11: During the test, pay attention to monitoring the intake air temperature of the auxiliary power unit (or the temperature near the intake port). If the temperature is close to the limit value, the auxiliary power unit shall be stopped according to the procedure. After the temperature returns to the ambient temperature, the test shall be carried out according to Step 3.2 to Step 3.3. Step 3.12: After completing the commissioning test, close the insulation cover 4 of the auxiliary power unit.

[0045] After completing step 3, install the left side shell of the insulation cover (or close the insulation cover shell), and conduct a commissioning test under simulated high-altitude conditions according to step 4 below, which specifically includes the following process: Step 4.1: Close the atmospheric intake valve 911 and the direct exhaust atmospheric valve 912 completely; Step 4.2: Adjust the engine to throttle mode, and establish air supply conditions as required using the combination of negative temperature air supply valve 102, normal temperature air supply valve 101, and high temperature air supply valve 103. Establish engine air inlet temperature conditions (total intake temperature) using engine intake air regulating valve 111 and cabin temperature control regulating valve 112.T t ); Step 4.3: While establishing engine air conditions, fully open the auxiliary power unit air supply vent valve 114, adjust the opening of the auxiliary power unit air supply regulating valve 113 to keep the auxiliary power unit speed within the range that can be operated for a long time in order to adjust the required inlet temperature value, and then close the auxiliary power unit air supply vent valve 114. Step 4.4: Adjust the engine to slow speed and allow it to run stably for at least 2 minutes before stopping the engine; Step 4.5: When the engine is stopped, start the auxiliary power unit according to the starting procedure. During the starting process, adjust the auxiliary power unit air supply regulating valve 113 to ensure that the inlet pressure and air flow of the auxiliary power unit meet the operating requirements of the engine. The auxiliary power unit shall be in the minimum stable operating state for no less than 30 seconds. Step 4.6: Adjust the auxiliary power unit to the maximum stable operating state, and adjust the auxiliary power unit air supply regulating valve 113 to ensure that the inlet pressure and air flow of the auxiliary power unit meet the operating requirements of the engine, and the stable operation is not less than 10 seconds. Step 4.7: Adjust the auxiliary power unit air supply regulating valve 113 and the auxiliary power unit air supply vent valve 114 to ensure that the inlet conditions of the auxiliary power unit meet the specified test conditions. Step 4.8: During the process of establishing the intake conditions for the auxiliary power unit, adjust the engine intake regulating valve 111 and the ambient pressure regulating valve 115 to ensure that the engine air conditions meet the requirements (total intake temperature T). t Total intake pressure P t and environmental pressure P sch ); Step 4.9: Start the engine according to the (ground or air) starting procedure. During the starting process, monitor parameters such as auxiliary power unit speed, exhaust temperature and bleed air pressure, engine speed, fuel supply flow, engine exhaust temperature, starter disengagement speed and lubricating oil pressure. After the engine reaches idle, adjust the auxiliary power unit to the minimum stable operating state and maintain stable operation for no less than 30 seconds. If the engine does not need to conduct a starting test, stop the auxiliary power unit. If the engine still needs to conduct a starting test, keep the auxiliary power unit in the same operating state. Step 4.10: The engine should run stably at idle for at least 2 minutes; Step 4.11: If you need to start the engine again, adjust the auxiliary power unit to its maximum operating state and operate stably for no less than 10 seconds before starting the engine. Note that the continuous operating time of the auxiliary power unit shall not exceed its limit. After the auxiliary power unit stops after the start-up test is completed, maintain a certain opening of the auxiliary power unit air supply regulating valve 113 (keep the auxiliary power unit speed within the range that can be operated for a long time) to reduce its exhaust temperature. When the exhaust temperature drops to the allowable range, close the auxiliary power unit air supply regulating valve 113 and the auxiliary power unit air supply vent valve 114.

[0046] The method of the present invention is an integrated joint commissioning method. It constructs a physically isolated master-slave dual environment with independent parameters in a single sealed test chamber, realizing synchronous commissioning of the engine and APU under their respective typical high-altitude operating conditions, thereby improving test fidelity and system reliability.

[0047] Compared with traditional experimental methods, the method of the present invention has at least the following advantages: 1. Traditional commissioning methods for the preparation of air supply systems often rely on experience-based adjustments, lacking systematic guarantees for pipeline cleanliness and control accuracy. This invention employs a three-stage combined purging process—steady-state, pulsating, and venting—to thoroughly remove particulate matter and moisture. Furthermore, based on multi-condition calibration, a quantitative control model is established between the engine intake regulating valve opening and the total intake pressure, ambient pressure, and airflow. This forms a repeatable and highly accurate air supply commissioning and calibration system, significantly improving the reliability and consistency of high-altitude simulation.

[0048] 2. Traditional solutions for ground-based joint commissioning do not consider the impact of the insulation cover on the exhaust of the auxiliary power unit, often leading to operational abnormalities due to increased back pressure or heat accumulation. This invention specifies that during ground commissioning, one side of the insulation cover should be removed or the left and right sides should remain open to create an effective ventilation gap, ensuring free diffusion of exhaust. This operational procedure fundamentally solves the problem of poor exhaust during ground testing with the cover on, ensuring the smooth implementation of ground functional verification.

[0049] 3. Regarding high-altitude joint testing capabilities, traditional high-altitude simulation test chambers can only provide a single, uniform environment, failing to replicate the aerial conditions encountered by the auxiliary power unit and engine during actual flight, leading to distortion in joint testing. This invention, by independently controlling the main environment (managed by engine intake / cabin temperature / pressure valves) and the sub-environment (managed by APU-dedicated air supply / venting valves), achieves, for the first time, parallel simulation of dual high-altitude operating conditions within a single chamber. This successfully supports ground verification of key scenarios such as in-flight restart and high-altitude start-up, significantly reducing flight test risks and substantially expanding the capabilities of high-altitude simulation testing.

[0050] Obviously, those skilled in the art should understand that the steps of the above-described embodiments of the present invention can be implemented using general-purpose computing devices. They can be centralized on a single computing device or distributed across a network of multiple computing devices. Optionally, they can be implemented using device-executable program code, thereby storing them in a storage device for execution by a computing device. In some cases, the steps shown or described can be performed in a different order than those presented here, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, the embodiments of the present invention are not limited to any particular combination of hardware and software.

[0051] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, various modifications and variations can be made to the embodiments of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for joint commissioning of an engine in a test chamber based on an auxiliary power unit, wherein the test chamber (1) is a sealed structure, equipped with an atmospheric intake valve (911), a direct exhaust atmospheric valve (912), an engine intake regulating valve (111), and a chamber temperature control regulating valve (112), and is equipped with an engine (2) and an auxiliary power unit (3), characterized in that, The auxiliary power unit (3) is equipped with a dedicated air supply pipeline independent of the main air supply system of the engine (2). The dedicated air supply pipeline is equipped with an auxiliary power unit air supply regulating valve (113), an auxiliary power unit air supply vent valve (114) and an intake air environment parameter measurement system. An openable and closable heat insulation cover (4) is set around it to form a sub-simulation environment in the test chamber (1) that is physically isolated from the main environment of the engine (2), thermally decoupled and with independently controllable environmental parameters. The method includes the following steps in sequence: performing multi-mode joint purging on the dedicated air supply pipeline; constructing a mapping control model between the opening of the auxiliary power unit air supply regulating valve (113) of the auxiliary power unit (3) and the total intake pressure, ambient pressure and air flow; performing ground joint debugging on the auxiliary power unit (3) and the engine (2); and performing in-flight start-up and joint operation debugging on the engine (2).

2. The method for joint commissioning of an engine in a test chamber based on an auxiliary power unit according to claim 1, characterized in that, Gas is supplied by the ambient temperature gas supply valve (101). Under the condition that the negative temperature gas supply valve (102), the high temperature gas supply valve (103), the engine intake regulating valve (111) and the cabin temperature control regulating valve (112) are closed, steady-state purging, pulsating disturbance purging and high-pressure venting are carried out in sequence by controlling the auxiliary power unit gas supply regulating valve (113) and the auxiliary power unit gas supply venting valve (114).

3. The method for joint commissioning of an engine in a test chamber based on an auxiliary power unit according to claim 2, characterized in that, Close the auxiliary power unit air supply vent valve (114), slowly open the auxiliary power unit air supply regulating valve (113), and use a clean air source with a pressure not lower than the actual maximum working pressure to perform steady-state purging on the dedicated air supply pipeline. Maintain stable air supply pressure, control the auxiliary power unit air supply regulating valve (113) to reciprocate within the opening range of 20% to 80% with a preset minimum operating cycle, generate pressure pulsation to remove impurities attached to the dedicated air supply pipeline, and realize pulsation disturbance purging. The auxiliary power unit gas supply vent valve (114) is opened simultaneously and the opening of the auxiliary power unit gas supply regulating valve (113) is increased to not less than 50%. The residual pollutants in the dedicated gas supply pipeline are discharged through the auxiliary power unit gas supply vent valve (114) to the common exhaust channel or dedicated collection system in the test chamber (1) by high-speed airflow, so as to realize high-pressure venting and purging.

4. The method for joint commissioning of an engine in a test chamber based on an auxiliary power unit according to claim 1, characterized in that, Based on the dedicated air supply pipeline after purging, the auxiliary power unit air supply regulating valve (113) and the optional main environmental control valve are adjusted under different simulated high-altitude working conditions to make the measured air flow rate close to the theoretical requirement value. After each working condition stabilizes, the corresponding valve opening, total intake pressure, environmental pressure and flow rate data are recorded. Based on the recorded data, a mapping control model of the opening of the auxiliary power unit air supply regulating valve (113) with respect to the total intake pressure, environmental pressure and air flow rate is constructed using polynomial regression or neural network methods.

5. The method for joint commissioning of an engine in a test chamber based on an auxiliary power unit according to claim 1, characterized in that, With the insulation cover (4) in a non-closed state and the atmospheric intake valve (911) and the direct exhaust atmospheric valve (912) fully open, the auxiliary power unit (3) and the engine (2) are jointly debugged on the ground.

6. The method for joint commissioning of an engine in a test chamber based on an auxiliary power unit according to claim 5, characterized in that, The insulation cover (4) being in a non-closed state means removing one side of its shell or maintaining a ventilation gap between the left and right shells sufficient to ensure the free diffusion of exhaust from the auxiliary power unit (3).

7. The method for joint commissioning of an engine in a test chamber based on an auxiliary power unit according to claim 1, characterized in that, Under the condition that the heat insulation cover (4) is closed and the atmospheric intake valve (911) and the direct exhaust atmospheric valve (912) are closed, the main environmental parameters of the engine (2) and the sub-environmental parameters of the auxiliary power unit (3) are adjusted independently according to the mapping control model. The main environmental parameters are achieved by regulating the engine intake regulating valve (111) and the cabin temperature control regulating valve (112); the sub-environmental parameters are achieved by regulating the auxiliary power unit air supply regulating valve (113) and the auxiliary power unit air supply venting valve (114); thereby constructing a main-sub dual-environment parallel simulation state that meets the high-altitude flight conditions, and performing engine (2) in-flight start-up and joint operation debugging in this state.

8. The method for joint commissioning of an engine in a test chamber based on an auxiliary power unit according to claim 7, characterized in that, The test chamber (1) is also equipped with a high temperature gas supply valve (103), a normal temperature gas supply valve (101) and a negative temperature gas supply valve (102) to provide gas sources of different temperature levels to the main environment; the adjustment of the main environment parameters also includes regulating one or more of the high temperature gas supply valve (103), the normal temperature gas supply valve (101) and the negative temperature gas supply valve (102).

9. The method for joint commissioning of an engine in a test chamber based on an auxiliary power unit according to claim 1, characterized in that, Also includes: After the joint commissioning test is completed, the auxiliary power unit air supply regulating valve (113) is adjusted to a preset non-zero opening degree. The turbine and exhaust section hot end components of the auxiliary power unit (3) are forcibly cooled by the continuous clean airflow from the dedicated air supply pipeline until the exhaust temperature drops below the safety threshold. Then the auxiliary power unit air supply regulating valve (113) and the auxiliary power unit air supply vent valve (114) are closed.

10. The method for joint commissioning of an engine in a test chamber based on an auxiliary power unit according to claim 1, characterized in that, The sub-simulated environment formed in the test chamber (1) can be set to a working condition that is significantly different from or consistent with the main environment, so that the auxiliary power unit (3) and the engine (2) can operate simultaneously under the same or different typical high-altitude conditions, in order to verify their collaborative working ability in real flight.

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