Multistage dynamic air entraining test system of aircraft environment control system and control method
By designing a multi-stage dynamic bleed air test system, and utilizing a combination of a heating air supply section and a differential pressure regulation section, precise control of airflow temperature and pressure is achieved. This solves the problem of simulating the dynamic changes of bleed airflow during aircraft operation in existing technologies, and improves the accuracy and efficiency of environmental control system testing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- BEIHANG UNIV
- Filing Date
- 2026-03-09
- Publication Date
- 2026-05-26
AI Technical Summary
Existing bleed air simulation test systems are unable to simulate the dynamic changes in bleed airflow during aircraft operation, especially the dynamic changes in airflow when switching between multiple pressure levels, and cannot accurately simulate the actual operating environment of the environmental control system.
A multi-stage dynamic bleed air test system was designed, including a high-pressure gas source, a heating gas supply section, a differential pressure adjustment section, a back pressure exhaust section, a first bleed air section, and a second bleed air section. By setting up heating devices, cooling devices, and regulating valves, the system can achieve precise control of airflow temperature and pressure, and simulate the switching and dynamic changes of high-pressure and medium-pressure bleed air.
It can accurately simulate the operating conditions of the environmental control system when switching between different levels of bleed air, improve the accuracy of the test, adapt to changes in engine power, reduce test costs and floor space, and is suitable for ground testing of environmental control systems.
Smart Images
Figure CN122085976A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of aircraft testing technology, and in particular to a multi-stage dynamic bleed air testing system and control method for an aircraft environmental control system. Background Technology
[0002] The aircraft environmental control system (ECS) is a device that ensures the safety and comfort of aircraft crew and passengers, and provides a normal operating environment for onboard electronic equipment. When drawing air from the engine compressor, the ECS adjusts its bleed air source according to the current operating status of the engine compressor. Typically, the ECS first draws air from the low-pressure stage of the compressor; if the bleed air pressure in the low-pressure stage is insufficient, the ECS then draws air from the high-pressure stage of the compressor.
[0003] To test the performance of the environmental control system (ECS) in a ground-based laboratory, a bleed air simulation test device is used to bleed air from the ECS system. However, during aircraft operation, the temperature and pressure of the airflow at the compressor bleed air inlet change dynamically, and the temperature and pressure of the bleed airflow at different pressure levels also differ significantly. Current bleed air simulation test systems struggle to simulate the dynamic changes in bleed airflow during aircraft operation, and even more so to simulate the dynamic changes in airflow during bleed air switching between multiple pressure levels. Summary of the Invention
[0004] This invention provides a multi-stage dynamic bleed air test system and control method for an aircraft environmental control system, used to simulate the dynamic bleed air state of the environmental control system.
[0005] In a first aspect, the present invention provides a multi-stage dynamic bleed air test system for an aircraft environmental control system, comprising: High-pressure gas source, heating and gas supply section, differential pressure regulation section, back pressure exhaust section, first bleed section and second bleed section; The back pressure exhaust section and the second induced draft section are connected in parallel, and the air inlet side of the back pressure exhaust section and the air inlet side of the second induced draft section are respectively connected in series with the air outlet side of the differential pressure regulating section; the differential pressure regulating section and the first induced draft section are connected in parallel, and the air inlet side of the differential pressure regulating section and the air inlet side of the first induced draft section are respectively connected in series with the air outlet side of the heating gas supply section, and the air inlet side of the heating gas supply section is connected to the high-pressure gas source; The heating gas supply section is equipped with a first shut-off valve and a heating device, and the differential pressure regulating section is equipped with a second shut-off valve and a cooling device.
[0006] In one embodiment, the differential pressure regulating section includes a first branch and a second branch arranged in parallel. The inlet of the first branch is connected to the inlet of the second branch, and the outlet of the first branch is connected to the outlet of the second branch. The cooling device is connected to the second branch to cool the gas flowing into the second branch. A second shut-off valve is provided on both the first branch and the second branch to increase the flow resistance of the differential pressure regulating section.
[0007] In one embodiment, a first regulating valve is provided on the first branch and a second regulating valve is provided on the second branch. The first regulating valve and the second regulating valve are used to adjust the gas flow ratio of the first branch and the second branch according to the gas temperature on the outlet side of the differential pressure regulating section.
[0008] In one embodiment, the cooling device includes a first heat exchanger and a refrigerator. The first heat exchanger is disposed in the second branch, and the refrigerator is used to exchange heat with the gas in the second branch through the first heat exchanger to reduce the temperature of the gas in the second branch.
[0009] In one embodiment, the heating gas supply section includes a third branch and a fourth branch arranged in parallel, the inlet of the third branch being connected to the inlet of the fourth branch, and the outlet of the third branch being connected to the outlet of the fourth branch, wherein the heating device is disposed in the fourth branch to heat the gas flowing into the fourth branch.
[0010] In one embodiment, a first shut-off valve is provided on both the third branch and the fourth branch to increase the flow resistance of the heating gas supply section. In one embodiment, a third regulating valve is provided on the third branch and a fourth regulating valve is provided on the fourth branch. The third regulating valve and the fourth regulating valve are used to adjust the gas flow ratio of the third branch and the fourth branch according to the air temperature on the outlet side of the heating gas supply section.
[0011] In one embodiment, the heating device includes a second heat exchanger, a heater, and a fan. The second heat exchanger is disposed in the fourth branch. The fan is used to generate a heat exchange airflow that blows toward the second heat exchanger. The heater is used to heat the heat exchange airflow so as to use the heat exchange airflow to heat the gas in the fourth branch.
[0012] In one embodiment, the back pressure exhaust section is provided with a fifth regulating valve, which is used to adjust its opening degree according to the inlet gas pressure of the back pressure exhaust section.
[0013] Secondly, the present invention also provides a control method for controlling the aforementioned multi-stage dynamic bleed air test system, characterized in that it includes the following steps: Close the first shut-off valve, the second shut-off valve, and the back pressure exhaust section, and connect the outlet of the first bleed section to the high pressure bleed port of the environmental control system, and connect the outlet of the second bleed section to the medium pressure bleed port of the environmental control system. Switch the environmental control system to draw air from the high-pressure air inlet, gradually increase the opening of the first shut-off valve until the air pressure in the first air inlet section reaches the high-pressure air inlet pressure, and then lock the opening of the first shut-off valve. Switch the environmental control system to draw air from the medium-pressure air inlet, gradually increase the opening of the second shut-off valve until the air pressure in the second air inlet reaches the medium-pressure air inlet pressure, and then lock the opening of the second shut-off valve. Open the back pressure exhaust section and set the exhaust pressure of the back pressure exhaust section to the medium pressure bleed air pressure. Adjust the heating and gas supply section so that the bleed temperature of the first bleed section meets the temperature requirements of the high-pressure bleed port; Adjust the differential pressure regulating section to ensure that the bleed air temperature of the second bleed air section meets the temperature requirements of the medium-pressure bleed air inlet.
[0014] In one embodiment, adjusting the heating gas supply section to ensure that the bleed temperature of the first bleed section meets the temperature requirements of the high-pressure bleed port includes the following steps: Start the heating device in the heating gas supply section to heat the airflow in the fourth branch. Adjust the opening of the third and fourth regulating valves according to the temperature on the outlet side of the heating gas supply section so that the bleed gas temperature in the first bleed gas section meets the requirements. The differential pressure adjustment section, which ensures that the bleed air temperature of the second bleed air section meets the temperature requirements of the medium-pressure bleed air inlet, includes the following steps: Start the cooling device in the differential pressure regulating section to cool the airflow in the second branch. Adjust the opening of the first regulating valve and the second regulating valve according to the temperature on the outlet side of the differential pressure regulating section so that the bleed temperature of the second bleed section meets the requirements.
[0015] Compared with the prior art, the advantages of this invention are that a heating device is provided at the heating gas supply section, and a high-pressure gas source is connected to the air inlet of the heating gas supply section. When the gas flows to the environmental control system through the first bleed gas section at the outlet side of the heating gas supply section, a high-temperature and high-pressure bleed gas flow can be provided to the environmental control system through the first bleed gas section, simulating a high-pressure bleed gas state. At the same time, the high-pressure and high-temperature gas flow will flow to the differential pressure regulating section. Under the action of the second shut-off valve, the first regulating valve, the second regulating valve, and the cooling device in the differential pressure regulating section, a medium-pressure and medium-temperature gas with lower pressure and temperature can be formed, and the medium-pressure bleed gas can be simulated using the second bleed gas port. That is, this application can use a single system to simulate different levels of bleed gas, so that the operating conditions when switching bleed gas levels can be simulated during environmental control system testing. At the same time, during use, the power of the heating device can be adjusted to simulate the power change of the engine, thereby synchronously realizing the dynamic change of high-pressure bleed gas and medium-pressure bleed gas. In other words, the multi-stage dynamic bleed air test system provided in this application can provide multi-stage bleed air for the environmental control system, more accurately simulate the changes in the bleed air state of the environmental control system, and make the environmental control system test closer to the actual use environment. Attached Figure Description
[0016] The invention will now be described in more detail with reference to embodiments and the accompanying drawings.
[0017] Figure 1 This is a system block diagram of the multi-stage dynamic air-entraining test system in an embodiment of the present invention; Figure 2 This is a flowchart of the control method in an embodiment of the present invention.
[0018] Figure label: 1. High-pressure air source; 2. First fast regulating valve; 3. Exhaust valve; 4. First shut-off valve; 5. First air pressure sensor; 6. Third regulating valve; 7. Fourth regulating valve; 8. Second heat exchanger; 9. Heater; 10. Power regulator; 11. Fan; 12. Second fast regulating valve; 13. Second shut-off valve; 14. Second air pressure sensor; 15. First regulating valve; 16. Second regulating valve; 17. First heat exchanger; 18. Refrigeration unit; 19. Third fast regulating valve; 20. Fourth fast regulating valve; 21. Fifth fast regulating valve; 22. Fourth air pressure sensor; 23. Flow meter; 24. Second temperature sensor; 25. Third air pressure sensor; 26. Differential pressure sensor; 27. First temperature sensor. Detailed Implementation
[0019] The invention will now be further described with reference to the accompanying drawings.
[0020] See Figure 1As shown, this invention provides a multi-stage dynamic bleed air test system for an aircraft environmental control system, comprising: a high-pressure air source 1, a heating air supply section, a differential pressure regulating section, a back pressure exhaust section, a first bleed air section, and a second bleed air section. The back pressure exhaust section and the second bleed air section are connected in parallel, and the inlet side of the back pressure exhaust section and the inlet side of the second bleed air section are respectively connected in series with the outlet side of the differential pressure regulating section. The differential pressure regulating section and the first bleed air section are connected in parallel, and the inlet side of the differential pressure regulating section and the inlet side of the first bleed air section are respectively connected in series with the outlet side of the heating air supply section. The inlet side of the heating air supply section is connected to the high-pressure air source 1.
[0021] In other words, after the gas in the high-pressure gas source 1 flows into the intake side of the heating gas supply section, the airflow will flow from the outlet side of the heating gas supply section to the first induced draft section and the differential pressure regulating section respectively, and the gas in the differential pressure regulating section will flow to the exhaust back pressure side or the second induced draft side respectively.
[0022] A first shut-off valve 4 and a heating device are installed at the heating and gas supply section, and a second shut-off valve 13 and a cooling device are installed at the differential pressure regulation section.
[0023] It is understandable that by controlling the heating device, the temperature of the gas in the heating supply section can be heated to the temperature of the high-pressure bleed air inlet of the aircraft engine. The heated high-temperature and high-pressure gas will flow through the first bleed air section to the environmental control system, simulating the bleed air from the environmental control system to the high-pressure stage bleed air inlet.
[0024] Another portion of the heated, high-temperature, high-pressure gas flows into the differential pressure regulating section connected in parallel with the first bleed section. By installing a second shut-off valve 13, a first regulating valve 15, and a second regulating valve 16 in the differential pressure regulating section, a pressure difference can be created between the inlet and outlet sides of the section, ensuring that the gas pressure flowing into the second bleed section is lower than that in the first bleed section. Simultaneously, because a cooling device is installed in the differential pressure regulating section, the air temperature is reduced, allowing the second bleed section to simulate the intermediate bleed port of an engine, providing medium-pressure, medium-temperature gas to the environmental control system.
[0025] In other words, the multi-stage dynamic bleed air test system provided in this application can simulate both the high-level bleed air of the environmental control system (EHS) through the first bleed air section and the intermediate-level bleed air of the EHS through the second bleed air section. Simultaneously, the two bleed air types can be dynamically adjusted. For example, the air pressure of the first and second bleed air sections can be adjusted by regulating the first shut-off valve 4, the third regulating valve 6, and the fourth regulating valve 7. Furthermore, the air temperature of both the first and second bleed air sections can be adjusted by regulating the heating device. Compared to previous bleed air test systems that could only achieve single-pressure bleed air adjustment, the multi-stage dynamic bleed air test system provided in this application offers multiple levels of bleed air flow, thus facilitating the simulation of bleed air switching conditions in the EHS. In addition, the simultaneous dynamic adjustment of the two levels of bleed air flow better simulates the bleed air flow provided by the engine, thereby improving the accuracy of the test during aircraft EHS testing.
[0026] See Figure 1 As shown, in some implementations, the differential pressure regulating section includes a first branch and a second branch arranged in parallel. The inlet of the first branch is connected to the inlet of the second branch, and the outlet of the first branch is connected to the outlet of the second branch. A cooling device is connected to the second branch to cool the gas flowing into the second branch. A second shut-off valve 13 is provided on both the first and second branches to increase the flow resistance of the differential pressure regulating section.
[0027] In other words, when the high-temperature, high-pressure airflow from the heating and supply section flows into the differential pressure regulating section, part of the airflow exits from the first branch with its temperature remaining essentially unchanged, while the other part of the airflow passes through the second branch and is cooled by the cooling device. When the airflow in the first branch mixes with the airflow in the second branch, the temperature of the resulting mixture is lower than the air temperature of the first intake section. This creates a temperature difference between the supply air temperatures of the first and second intake sections.
[0028] On the other hand, since second shut-off valves 13 are installed on both the first and second branches, the gas pressure decreases as it passes through the second shut-off valves 13, resulting in the gas supply pressure of the second priming section being lower than that of the first priming section. In this application, a first regulating valve 15 is also installed on the first branch, and a second regulating valve 16 is installed on the second branch. The first regulating valve 15 and the second regulating valve 16 not only achieve flow distribution between the first and second branches but also work in conjunction with the second shut-off valve 13 to reduce gas pressure.
[0029] In some implementations, the flow resistance in the first branch can be made approximately equal to that in the second branch by adjusting the second shut-off valves 13 on the first and second branches. Specifically, this can be achieved by fully opening the first regulating valve 15 on the first branch and the second regulating valve 16 on the second branch, and then adjusting the two second shut-off valves 13 based on real-time measurements of the pressure drop in the first and second branches until the pressure drop in the first and second branches is equal at the same time. This indicates that the flow resistance in the first and second branches is approximately equal. When the pressure in the first bleed section is adjusted by changing the first shut-off valve 4 to simulate the pressure at the high-level bleed port, the pressure in the second bleed section more closely matches the pressure at the intermediate-level bleed port under the corresponding operating conditions.
[0030] See Figure 1 As shown, in some implementations, a first regulating valve 15 is provided on the first branch and a second regulating valve 16 is provided on the second branch. The first regulating valve 15 and the second regulating valve 16 are used to adjust the gas flow ratio of the first branch and the second branch according to the gas temperature on the outlet side of the differential pressure regulating section.
[0031] By increasing the opening of the first regulating valve 15, more airflow can enter the first branch, resulting in less airflow being cooled by the cooling device. This leads to a higher temperature of the mixture formed after the gas in the first branch mixes with the gas in the second branch compared to before the opening of the first regulating valve 15 was increased. In other words, when it is necessary to lower the gas temperature at the outlet of the differential pressure regulating section, the opening of the first regulating valve 15 can be decreased, or the opening of the second regulating valve 16 can be increased, allowing more gas to be cooled by the cooling device. Conversely, when it is necessary to increase the gas temperature at the outlet of the differential pressure regulating section, the opening of the first regulating valve 15 can be increased, or the opening of the second regulating valve 16 can be decreased, allowing less gas to be cooled by the cooling device.
[0032] Combination Figure 1 It is known that a first temperature sensor 27 is also installed in the differential pressure regulating section. The first temperature sensor 27 is used to measure the air temperature of the mixed airflow formed by the first branch and the second branch. The first regulating valve 15 and the second regulating valve 16 are electrically connected to the first temperature sensor 27, so as to determine the opening degree of the regulating valve according to the difference between the temperature value measured by the first temperature sensor 27 and the required medium-pressure bleed air temperature value.
[0033] See Figure 1 As shown, a second fast regulating valve 12 is also provided in the differential pressure regulating section. The second fast regulating valve 12 is electrically connected to the second air pressure sensor 14 provided at the end of the differential pressure regulating section. When the pressure fluctuates, the air pressure at the second air intake section can be stabilized at the required air pressure value by adjusting the second fast regulating valve 12.
[0034] like Figure 1As shown, in some implementations, the cooling device includes a first heat exchanger 17 and a refrigerator 18. The first heat exchanger 17 is located in the second branch, and the refrigerator 18 is used to exchange heat with the gas in the second branch through the first heat exchanger 17, thereby reducing the temperature of the gas in the second branch. In use, the refrigerator 18 can be used to cool the gas in the second branch. After the gas in the second branch mixes with the first gas, the temperature of the mixed gas is lower than the temperature of the gas in the first branch, thus achieving gas cooling. During cooling, the temperature of the second bleed section can be adjusted by regulating the opening of the first regulating valve 15 and the second regulating valve 16, thereby controlling the flow ratio in the first and second branches. For example, when it is necessary to lower the temperature of the second bleed section to a lower temperature, the opening of the second regulating valve 16 in the second branch can be increased, allowing more gas to be cooled by the first heat exchanger 17 from the second branch, thus increasing the proportion of low-temperature gas when the first and second branches are mixed, resulting in a lower temperature of the mixed gas.
[0035] See Figure 1 As shown, in some implementations, the heating gas supply section includes a third branch and a fourth branch arranged in parallel. The inlet of the third branch is connected to the inlet of the fourth branch, and the outlet of the third branch is connected to the outlet of the fourth branch. A heating device is installed in the fourth branch to heat the gas flowing into the fourth branch.
[0036] In other words, the gas passing through the third branch is not directly heated by the heating device, while the gas in the fourth branch is heated. After the gas in the fourth branch is heated, the resulting high-temperature gas mixes with the room-temperature gas in the third branch, ultimately producing a high-temperature gas. This simulates the high-temperature bleed air produced by an engine.
[0037] See Figure 1 As shown, in some implementations, a first shut-off valve 4 is installed on both the third and fourth branches to increase the flow resistance of the heating gas supply section. By installing the first shut-off valve 4 on the third and fourth branches, the flow resistance of the gas can be increased, and the gas pressure at the end of the heating gas supply section can be stabilized within the gas pressure range required by the first induced draft section.
[0038] See Figure 1 As shown, a second quick-regulating valve 12 is installed at the outlet of the first air intake section, and a second pressure sensor 14 is installed at the end of the heating air supply section. The second quick-regulating valve 12 is electrically connected to the second pressure sensor 14. The opening degree of the second quick-regulating valve 12 can be controlled according to the air pressure measured by the second pressure sensor 14 to adjust the outlet air pressure of the first air intake section to the set air pressure.
[0039] See Figure 1As shown, in some implementations, a third regulating valve 6 is provided on the third branch, and a fourth regulating valve 7 is provided on the fourth branch. The third regulating valve 6 and the fourth regulating valve 7 are used to adjust the gas flow ratio between the third and fourth branches according to the air temperature at the outlet of the heating gas supply section. That is, by adjusting the third regulating valve 6 and the fourth regulating valve 7, more gas can be passed through the third or fourth branch, thereby controlling the ratio of high-temperature gas to room-temperature gas. When the temperature sensor on the outlet side of the heating gas supply section measures a temperature lower than the set temperature, the opening of the fourth regulating valve 7 can be increased, or the opening of the third regulating valve 6 can be decreased, allowing more gas to pass through the fourth branch and be heated by the heating device, thereby increasing the air temperature at the outlet of the heating gas supply section. Conversely, when the second temperature sensor 24 on the outlet side of the heating gas supply section measures a temperature higher than the set temperature, the opening of the fourth regulating valve 7 can be decreased, or the opening of the third regulating valve 6 can be increased, allowing more gas to pass through the third branch, thereby decreasing the air temperature at the outlet of the heating gas supply section.
[0040] See Figure 1 As shown, in some implementations, the heating device includes a second heat exchanger 8, a heater 9, and a fan 11. The second heat exchanger 8 is located in the fourth branch. The fan 11 is used to generate a heat exchange airflow that blows towards the second heat exchanger 8. The heater 9 is used to heat the heat exchange airflow to heat the gas in the fourth branch. That is, the heater 9 heats the air to form a heat exchange airflow, and then uses the heat exchange airflow to heat the gas in the fourth branch. The heater 9 can be an electric heater 9, and it can be connected to a power regulator 10. The power regulator 10 adjusts the power of the heater 9, thereby adjusting the gas temperature in the first bleed section by increasing or decreasing the power of the heater 9.
[0041] See Figure 1 As shown, in some implementations, the back pressure exhaust section is equipped with a fifth quick-adjusting valve 21, which is used to adjust its opening degree according to the inlet air pressure of the back pressure exhaust section. Specifically, a first air pressure sensor 5 is provided at the inlet of the back pressure exhaust section, and the first air pressure sensor 5 is electrically connected to the fifth quick-adjusting valve 21.
[0042] Combination Figure 1It is known that the air pressure at the first air pressure sensor 5 is approximately equal to the air pressure at the second bleed section. During the adjustment process, the stable air pressure parameter of the fifth quick-regulating valve 21 can be set to the medium-pressure air pressure required by the environmental control system. When the environmental control system only receives gas from the first bleed section and does not draw gas from the second bleed section, the excess gas can be discharged using the back pressure exhaust section. Similarly, when the environmental control system only receives gas from the second bleed section and does not draw gas from the first bleed section, the excess gas can also be discharged using the back pressure exhaust section. Furthermore, the back pressure exhaust section can maintain a stable back pressure environment, avoiding air pressure fluctuations between the first and second bleed sections when the environmental control system switches bleed sources.
[0043] join Figure 1 As shown, in some implementations, a first quick-regulating valve 2 is also provided between the heating device and the high-pressure gas source 1, and a flow meter 23 is provided on the outlet side of the first quick-regulating valve 2. By adjusting the opening of the first quick-regulating valve 2, the gas flow rate to the heating device can be adjusted. It can be understood that the flow rate measured by the flow meter 23 is the sum of the flow rate of the first bleed section, the flow rate of the second bleed section, and the flow rate of the exhaust back pressure section.
[0044] Combination Figure 1 It is known that the first quick-regulating valve 2 is electrically connected to the fourth pressure sensor 22 on its outlet side. The opening of the first quick-regulating valve 2 can be adjusted by the pressure value measured by the fourth pressure sensor 22, thereby ensuring that the pressure of the gas flowing out of the first quick-regulating valve 2 reaches the set value. Furthermore, an exhaust valve 3 is also provided between the high-pressure gas source 1 and the exhaust port of the exhaust valve 3, allowing excess gas to be discharged. Compared to using only the first quick-regulating valve 2 to regulate the pressure, the additional exhaust valve 3 improves the accuracy of pressure regulation, allowing the pressure and flow rate to be accurately adjusted to the target value. An exhaust treatment device can also be connected to the tail of the exhaust valve 3 to treat the exhaust gas, thereby reducing exhaust noise and pollution.
[0045] See Figure 1 As shown, a third quick-regulating valve 19 is installed at the outlet of the first bleed section. The third quick-regulating valve 19 is electrically connected to a third pressure sensor 25, which is installed on the heating and gas supply section. The third quick-regulating valve 19 can adjust its opening according to the pressure fluctuation of the heating and gas supply section, thereby avoiding pressure fluctuations in the bleed air of the first bleed section caused by pressure fluctuations in the heating and gas supply section.
[0046] like Figure 1 As shown, in some implementations, a fourth quick-regulating valve 20 is provided at the outlet of the second bleed air section. When it is not necessary to use the second bleed air section to provide bleed air to the environmental control system, the fourth quick-regulating valve 20 can be closed.
[0047] Combination Figure 1It is known that a second quick-regulating valve 12 is also provided in the differential pressure regulating section. The second quick-regulating valve 12 is located on the air inlet side of the cooling device and is connected to a differential pressure sensor 26. The differential pressure sensor 26 is also connected to two second air pressure sensors 14. One second air pressure sensor 14 is located at the end of the differential pressure regulating section, while the other second air pressure sensor 14 is located at the beginning of the differential pressure regulating section. By connecting the differential pressure sensor 26 to the two second air pressure sensors 14, the differential pressure sensor 26 can obtain the air pressure difference between the beginning and end of the differential pressure regulating section. When the air pressure difference measured by the differential pressure sensor 26 is equal to the difference between the high-pressure bleed air pressure and the medium-pressure bleed air pressure, it indicates that the opening of the second quick-regulating valve 12 is appropriate. If the air pressure difference measured by the differential pressure sensor 26 differs from the difference between the high-pressure bleed air pressure and the medium-pressure bleed air pressure, the air pressure difference between the two ends of the differential pressure regulating section can be adjusted to meet the requirements. In this application, the differential pressure at both ends of the differential pressure adjustment section can be stabilized by using the second fast regulating valve 12 connected to the differential pressure sensor 26.
[0048] See Figure 1 as well as Figure 2 As shown, the present invention also provides a control method for controlling the above-mentioned multi-stage dynamic bleed air test system, which includes the following steps: Close the first shut-off valve 4, the second shut-off valve 13 and the back pressure exhaust section, and connect the outlet of the first bleed section to the high pressure bleed port of the environmental control system, and connect the outlet of the second bleed section to the medium pressure bleed port of the environmental control system. Switch the environmental control system to draw air from the high-pressure air inlet, gradually increase the opening of the first shut-off valve 4 until the air pressure in the first air inlet section reaches the high-pressure air inlet pressure, and then lock the opening of the first shut-off valve 4. Switch the environmental control system to draw air from the medium-pressure air intake port, gradually increase the opening of the second shut-off valve 13 until the air pressure of the second air intake section reaches the medium-pressure air intake pressure, and then lock the opening of the second shut-off valve 13. Open the back pressure exhaust section and set the exhaust pressure of the back pressure exhaust section to the medium pressure bleed air pressure. Adjust the heating and gas supply section so that the bleed temperature of the first bleed section meets the temperature requirements of the high-pressure bleed port; Adjust the differential pressure regulating section to ensure that the bleed air temperature of the second bleed air section meets the temperature requirements of the medium-pressure bleed air inlet.
[0049] Through the above steps, the exhaust gas pressure and exhaust temperature of the first bleed section can meet the requirements of the high-pressure bleed port in the environmental control system, while the exhaust gas pressure and exhaust temperature of the second bleed section can meet the requirements of the medium-pressure bleed port in the environmental control system.
[0050] During the temperature adjustment process, the heating device can be used first to adjust the air temperature of the heating gas supply section, and then the cooling device can be used to adjust the temperature of the differential pressure adjustment section, thus avoiding multiple adjustments to the gas temperature of the differential pressure adjustment section.
[0051] It should be noted that, in this application, a constant flow resistance can be maintained between the first and second bleed air sections via the second shut-off valve 13. Therefore, during subsequent pressure adjustment, only the exhaust back pressure needs to be adjusted, eliminating the need to adjust the first shut-off valve 4 and the second shut-off valve 13. This enables coordinated pressure regulation of the first and second bleed air sections. Compared to setting up two separate bleed air systems with different pressure levels, this is more convenient for adapting to dynamic pressure bleed air.
[0052] Furthermore, compared to building two separate bleed air systems, this application can utilize a single high-pressure gas source 1 to achieve two-stage pressure bleed air, significantly reducing the cost, footprint, and subsequent relocation difficulty of the test system. It is highly suitable for ground testing of environmental control systems.
[0053] In some implementations, adjusting the heating gas supply section to ensure that the bleed gas temperature of the first bleed gas section meets the temperature requirements of the high-pressure bleed gas port includes the following steps: The heating device in the heating gas supply section is activated to heat the airflow in the fourth branch. The opening of the third regulating valve 6 and the fourth regulating valve 7 is adjusted according to the temperature on the outlet side of the heating gas supply section so that the bleed gas temperature in the first bleed gas section meets the requirements. In other words, the temperature of the first bleed section can be regulated not only by adjusting the power of the heating device, but also by adjusting the opening of the third regulating valve 6 and the fourth regulating valve 7 to regulate the amount of gas flowing into the heating device, thereby regulating the temperature of the outlet side of the heating supply section. Specifically, when it is necessary to increase the temperature of the first bleed section, the opening of the third regulating valve 6 is reduced or the opening of the fourth regulating valve 7 is increased, so that more gas in the heating supply section passes through the fourth branch and is heated by the heating device, ultimately increasing the bleed temperature of the first bleed section. Compared with temperature regulation achieved by adjusting the power of the heating device, the method of controlling the airflow distribution ratio can achieve temperature regulation more quickly and has a faster response speed.
[0054] The differential pressure adjustment section, which ensures that the bleed air temperature of the second bleed air section meets the temperature requirements of the medium-pressure bleed air inlet, includes the following steps: Start the cooling device in the differential pressure regulating section to cool the airflow in the second branch. Adjust the opening of the first regulating valve and the second regulating valve according to the temperature on the outlet side of the differential pressure regulating section so that the bleed temperature of the second bleed section meets the requirements.
[0055] In other words, this application not only allows for temperature regulation of the second bleed section by adjusting the power of the cooling device, but also by adjusting the first regulating valve 15 and the second regulating valve 16 to adjust the airflow distribution ratio between the first and second branches, ultimately achieving temperature regulation of the second bleed section. For example, when it is necessary to lower the temperature of the second bleed section to meet the temperature requirements of the medium-pressure bleed port, the opening of the first regulating valve 15 can be reduced, or the opening of the second regulating valve 16 can be increased, so that more gas undergoes cooling treatment, thereby reducing the outlet temperature of the differential pressure regulating section until the temperature requirements of the medium-pressure bleed port are met.
[0056] Of course, each time the bleed air temperature of the first bleed air section is adjusted, the intake air temperature of the differential pressure regulating section will change synchronously. Therefore, after each adjustment of the bleed air temperature of the first bleed air section, it is necessary to confirm whether the bleed air temperature of the second bleed air section meets the requirements. If the bleed air temperature of the second bleed air section deviates significantly, it is necessary to adjust the power of the first regulating valve 15, the second regulating valve 16, or the cooling device to ensure that the bleed air temperature of the second bleed air section meets the requirements.
[0057] Of course, although this application only describes a two-stage bleed air test system, in practice, a differential pressure regulation stage with a shut-off valve can be set after the differential pressure regulation stage. The intake side of the second bleed air stage is located before the differential pressure regulation stage, while the back pressure exhaust stage is connected to the exhaust side of the differential pressure regulation stage. Simultaneously, a bleed air port is led out at the end of the latter differential pressure regulation stage to achieve low-pressure bleed air, thereby simulating a three-stage bleed air system. A three-stage bleed air system built according to this idea can achieve synchronous changes in the three-stage bleed air pressure, thus accurately simulating the pressure changes at the three-stage bleed air ports of an engine.
[0058] As mentioned above, in this application, the gas flow rate entering the first and second branches can be controlled by adjusting the opening degree of the first regulating valve 15 and the second regulating valve 16, thereby achieving the adjustment of the outlet gas temperature of the second bleed section. Furthermore, the gas flow rate entering the third and fourth branches can be controlled by adjusting the opening degree relationship of the third regulating valve 6 and the fourth regulating valve 7, thereby achieving the adjustment of the air temperature of the first bleed section.
[0059] Understandably, once the opening degrees of the first shut-off valve 4 and the second shut-off valve 13 are determined, they are no longer adjusted to simulate the constant flow resistance between the high and medium air intake ports. When it is necessary to adjust the flow rate of the two air intake ports later, the total flow rate can be changed by adjusting the first quick-adjusting valve 2. This causes a corresponding change in the amount of gas flowing into the first and second air intake sections.
[0060] Although the invention has been described with reference to preferred embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the invention. In particular, the technical features mentioned in the various embodiments can be combined in any manner as long as there is no structural conflict. The invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.
Claims
1. A multi-stage dynamic bleed air test system for an aircraft environmental control system, characterized in that, It includes: High-pressure gas source, heating and gas supply section, differential pressure regulation section, back pressure exhaust section, first bleed section and second bleed section; The back pressure exhaust section and the second induced draft section are connected in parallel, and the air inlet side of the back pressure exhaust section and the air inlet side of the second induced draft section are respectively connected in series with the air outlet side of the differential pressure regulating section; the differential pressure regulating section and the first induced draft section are connected in parallel, and the air inlet side of the differential pressure regulating section and the air inlet side of the first induced draft section are respectively connected in series with the air outlet side of the heating gas supply section, and the air inlet side of the heating gas supply section is connected to the high-pressure gas source; The heating gas supply section is equipped with a first shut-off valve and a heating device, and the differential pressure regulating section is equipped with a second shut-off valve and a cooling device.
2. The multi-stage dynamic air-entraining test system according to claim 1, characterized in that, The differential pressure regulating section includes a first branch and a second branch arranged in parallel. The inlet of the first branch is connected to the inlet of the second branch, and the outlet of the first branch is connected to the outlet of the second branch. The cooling device is connected to the second branch to cool the gas flowing into the second branch. Both the first branch and the second branch are equipped with a second shut-off valve to increase the flow resistance of the differential pressure regulating section.
3. The multi-stage dynamic air-entraining test system according to claim 2, characterized in that, A first regulating valve is provided on the first branch, and a second regulating valve is provided on the second branch. The first regulating valve and the second regulating valve are used to adjust the gas flow ratio of the first branch and the second branch according to the gas temperature on the outlet side of the differential pressure regulating section.
4. The multi-stage dynamic air evoked experimental system according to claim 3, characterized in that, The cooling device includes a first heat exchanger and a refrigerator. The first heat exchanger is installed in the second branch, and the refrigerator is used to exchange heat with the gas in the second branch through the first heat exchanger to reduce the temperature of the gas in the second branch.
5. The multi-stage dynamic air evoked experimental system according to any one of claims 1-4, characterized in that, The heating gas supply section includes a third branch and a fourth branch arranged in parallel. The inlet of the third branch is connected to the inlet of the fourth branch, and the outlet of the third branch is connected to the outlet of the fourth branch. The heating device is arranged in the fourth branch to heat the gas flowing into the fourth branch.
6. The multi-stage dynamic air evoked experimental system according to claim 5, characterized in that, Both the third and fourth branches are equipped with first shut-off valves to increase the flow resistance of the heating gas supply section.
7. The multi-stage dynamic air evoked experimental system according to claim 5, characterized in that, A third regulating valve is provided on the third branch, and a fourth regulating valve is provided on the fourth branch. The third regulating valve and the fourth regulating valve are used to adjust the gas flow ratio of the third branch and the fourth branch according to the air temperature on the outlet side of the heating gas supply section.
8. The multi-stage dynamic air evoked experimental system according to claim 5, characterized in that, The heating device includes a second heat exchanger, a heater, and a fan. The second heat exchanger is disposed in the fourth branch. The fan is used to generate a heat exchange airflow that blows toward the second heat exchanger. The heater is used to heat the heat exchange airflow so as to use the heat exchange airflow to heat the gas in the fourth branch.
9. The multi-stage dynamic air evoked experimental system according to any one of claims 1-4, characterized in that, The back pressure exhaust section is equipped with a fifth regulating valve, which is used to adjust its opening degree according to the inlet air pressure of the back pressure exhaust section.
10. A control method for controlling a multi-stage dynamic bleed air test system as described in any one of claims 1-9, characterized in that, It includes the following steps: Close the first shut-off valve, the second shut-off valve, and the back pressure exhaust section, and connect the outlet of the first bleed section to the high pressure bleed port of the environmental control system, and connect the outlet of the second bleed section to the medium pressure bleed port of the environmental control system. Switch the environmental control system to draw air from the high-pressure air inlet, gradually increase the opening of the first shut-off valve until the air pressure in the first air inlet section reaches the high-pressure air inlet pressure, and then lock the opening of the first shut-off valve. Switch the environmental control system to draw air from the medium-pressure air inlet, gradually increase the opening of the second shut-off valve until the air pressure in the second air inlet reaches the medium-pressure air inlet pressure, and then lock the opening of the second shut-off valve. Open the back pressure exhaust section and set the exhaust pressure of the back pressure exhaust section to the medium pressure bleed air pressure. Adjust the heating and gas supply section so that the bleed temperature of the first bleed section meets the temperature requirements of the high-pressure bleed port; Adjust the differential pressure adjustment section to ensure that the bleed air temperature of the second bleed air section meets the temperature requirements of the medium-pressure bleed air port; The process of adjusting the heating and gas supply section to ensure that the bleed temperature of the first bleed section meets the temperature requirements of the high-pressure bleed port includes the following steps: Start the heating device in the heating gas supply section to heat the airflow in the fourth branch. Adjust the opening of the third and fourth regulating valves according to the temperature on the outlet side of the heating gas supply section so that the bleed gas temperature in the first bleed gas section meets the requirements. The differential pressure adjustment section, which ensures that the bleed air temperature of the second bleed air section meets the temperature requirements of the medium-pressure bleed air inlet, includes the following steps: Start the cooling device in the differential pressure regulating section to cool the airflow in the second branch. Adjust the opening of the first regulating valve and the second regulating valve according to the temperature on the outlet side of the differential pressure regulating section so that the bleed temperature of the second bleed section meets the requirements.