Corrosion resistance test device and test method for aviation turbojet and turbofan engines

Abstract

The invention provides an aviation turbojet and turbofan engine corrosion resistance test device and test method. The device comprises an air inlet unit, a temperature adjusting unit, a humidity adjusting unit, a salt mist mixing adjusting unit, a dynamic salt mist sampling unit, a salt mist protection cabin, an air adjusting unit, an exhaust unit and a measurement and control unit. In the engine operation stage, the exhaust injection effect of a test engine is used as a system air inlet main driving power source, and the air supply flow stability of the system in different operation states of the engine is realized by combining the adjustment of an exhaust fan; different flow path designs are carried out according to test requirements of different stages of an engine corrosion resistance test; and the risk of system control failure caused by the fact that a sensor in the protection cabin is low in reliability due to the long-term salt mist airflow effect is reduced while it is guaranteed that the environment in the protection cabin meets the test requirement.

Description

Technical Field

[0001] The invention belongs to the field of engine testing, and in particular relates to a corrosion resistance test device and a test method for aviation turbojet and turbofan engines. Background Art

[0002] When aircraft engines fly in coastal environments, the harsh and changeable climate environment of the ocean and coastal areas, such as high temperature, humidity, and salt spray, will cause serious corrosion to the flow components on the engine. This corrosion will lead to deterioration of the engine's aerodynamic performance and affect the engine's structural strength and fatigue life. On the other hand, higher salt content will be adsorbed by the liquid film on the engine surface when the engine is working, causing scaling on the engine's flow surface. Scaling will increase the surface roughness and the contact area with the air, further accelerating the scaling rate. Surface scaling will cause serious wear of the engine's rotating parts, affecting the engine's compression ratio and efficiency, thereby causing a decline in engine performance.

[0003] According to GJB 241A-2010 and GJB 242A-2018, nearly all types of aircraft engines, including turboshafts, turboprops, turbojets, and turbofans, must undergo corrosion resistance testing to assess performance changes under environmental conditions experienced during operation, transportation, and storage. Currently, relevant corrosion resistance test facilities have been constructed for turboshaft and turboprop engines, and corrosion resistance development or qualification testing is performed using these facilities. Compared to turboshaft and turboprop engines, turbojets and turbofans possess higher intake and exhaust flow rates and a more pronounced tail jet ejection effect. Intake flow rates can reach hundreds of kg / s, and ejection ratios can range from 5:1 to 8:1. Continuing to use the same corrosion resistance test facility technology for turboshaft and turboprop engines—using a front-end air supply blower to actively supply air to meet the engine's combined intake and exhaust ejection requirements—would create significant technical challenges and cost pressures for environmental simulation during engine operation.

[0004] Therefore, based on the intake and exhaust characteristics of turbojet and turbofan engines, a new technical route is adopted to develop a set of corrosion resistance test equipment for aviation turbojet and turbofan engines, and reduce construction and use costs. This is of great significance for effectively carrying out corrosion resistance tests of aviation turbojet and turbofan engines, thereby meeting the navy's needs for engine adaptability design and performance assessment in the marine environment and improving the reliability of naval engines. Summary of the Invention

[0005] The purpose of the present invention is to provide a corrosion resistance test device for aviation turbojet and turbofan engines. According to the intake and exhaust characteristics of turbojet and turbofan engines themselves, a new technical route is adopted to develop a corrosion resistance test device for aviation turbojet and turbofan engines. That is, the exhaust ejection effect of the turbojet and turbofan engines is fully utilized as the main driving power source for the engine intake, and the closed-loop feedback control of various environmental parameters is used to achieve stable and controllable simulated environment, thereby reducing construction and use costs and facilitating the effective implementation of corrosion resistance tests for aviation turbojet and turbofan engines.

[0006] The present invention provides a corrosion resistance test device suitable for aviation turbojet and turbofan engines. The test device comprises: an air intake unit, a temperature adjustment unit, a humidity adjustment unit, a salt spray mixing adjustment unit, a dynamic salt spray sampling unit, a salt spray protection cabin, an air conditioning unit, an exhaust unit and a measurement and control unit.

[0007] The air intake unit is primarily responsible for supplying air to the system, providing a stable flow during engine operation or transportation. This not only meets the engine's intake needs and the need for airflow over its exterior surfaces during operation, but also provides an air carrier for system temperature, humidity, and salt spray simulation. The air intake unit primarily consists of an intake duct, an air intake control grille, an auxiliary air supply fan, an exhaust fan, blind plates, and valves. By switching valves in different positions, different airflow paths are formed to meet the air supply requirements of different engine test stages. Exhaust fan regulation, combined with the engine's own operating ejection effect, ensures a stable air supply during engine operation. The coordination of the auxiliary air supply fan and exhaust fan ensures a stable air supply for testing and assessment when the engine is not operating. All system piping utilizes a double-layer thermal insulation structure, consisting of an inner layer of slightly positive pressure-bearing non-metallic, corrosion-resistant material, a middle layer of polyurethane foam insulation, and an outer layer wrapped in a thin steel plate structure.

[0008] The temperature control unit, consisting of a heater, temperature sensor, and power regulator, simulates the ambient engine intake air temperature. The heater is installed within the intake tower to minimize the impact of additional resistance in the main intake duct during engine intake. Before the test begins, the heater can be pre-activated to preheat and control the surface temperature, minimizing significant heating control lag during high-flow intake. During engine operation, ambient air is heated and controlled by the heater in the intake tower, creating a heated flow that meets test requirements before entering the main intake duct. The heater maintains constant power according to the intake volume at maximum engine thrust, preventing divergence or significant fluctuations in system temperature control caused by heating lag.

[0009] The humidity control unit consists of a water supply, a water softener, a steam generator, a distribution cylinder, a steam control valve, and a steam injector. During the test, tap water was supplied by the water supply, softened by the water softener, and then fed into the steam generator to form dry steam. This dry steam was then transported to different locations via distribution cylinders. Steam control valves were installed on each steam branch line to control the amount of steam injected, thereby effectively controlling the humidity of the air supply. The steam injectors were designed to be located behind the wind speed sensor in the main air intake duct and in the air handling unit. Multiple steam nozzles were installed on the steam injectors, and the spray direction was opposite to the incoming air flow, facilitating rapid steam absorption.

[0010] The salt spray mixing and conditioning unit consists of a salt spray generator and a salt spray injection device, primarily designed to simulate the airborne salt spray concentration found in real coastal environments. Salt spray generation primarily utilizes the principle of atomizing salt water with compressed air. The salt spray generator provides compressed air and salt water, while the salt spray injection device comprises multiple spray booms, each equipped with a pair of atomizing nozzles. The amount of salt spray injected is controlled by the number of active spray booms and the salt water flow rate. The direction of salt spray injection aligns with the incoming airflow to prevent salt spray from depositing on the spray boom surfaces, which could cause control errors.

[0011] The dynamic salt spray sampling unit consists of a gas sampling probe and a salt spray absorption analysis device. The gas sampling probe is installed on the main air duct section. The salt spray absorption analysis device samples the gas in the air duct through the sampling probe and performs absorption analysis to detect and calculate the salt content in the dynamic air. The sampling probe can adopt single-point or multi-point averaging.

[0012] The salt spray chamber, used to encase the test engine and process air intake, features a body-of-revolution design. The clearance between the chamber wall and the engine's exterior surface is designed to ensure the engine's ability to eject external flow. The chamber's end is open and extends beyond the engine's tail nozzle, ensuring that the engine's exhaust flow flows between the chamber and the engine's exterior. The chamber is constructed of corrosion-resistant metal to ensure structural strength and temperature resistance. The exterior is covered with flame-retardant insulation to minimize heat leakage from the chamber wall.

[0013] The air conditioning unit is used to simulate the high temperature and high humidity environment during engine storage. The air conditioning unit adopts a skid-mounted integrated structure. The inlet and return air ducts are connected to the reserved interface of the protection cabin to form a loop. The air conditioning unit contains a centrifugal fan, an air heater and a steam injector. The centrifugal fan is used to circulate the air flow in the protection cabin, and the air flow temperature is adjusted by the heater, and the air flow humidity is adjusted by the steam injector, so that the temperature and humidity environment in the protection cabin finally meet the requirements.

[0014] The exhaust unit consists of an exhaust pipe and an exhaust fan. The high-speed and high-temperature exhaust gas generated when the engine is working directly enters the exhaust pipe and is discharged after passing through the engine exhaust tower. When the engine is not working, the test gas is discharged through the exhaust fan.

[0015] The measurement and control unit is responsible for controlling the flow path switching and environmental parameter control of the aircraft engine corrosion resistance test equipment, ensuring that parameters such as air supply volume, temperature, pressure, humidity, and salt spray concentration meet the requirements of the offshore environment during engine testing. It also collects data on monitoring parameters and equipment operating status, and implements data storage and safety protection functions. It should be noted that temperature and humidity sensors are installed before the salt spray injector on the main line and around the engine in the protective cabin. The measured values of the temperature and humidity sensors in the protective cabin are used as the primary control targets, and the temperature and humidity sensors on the main line are used as safety protection control targets. The specific strategy is that if the measured values of the temperature / humidity sensors in the protective cabin deviate from the temperature / humidity measured values on the main line by more than a certain safety set value, the temperature or humidity sensor in the protective cabin is determined to have failed. The measurement and control unit automatically switches the temperature or humidity on the main line as the primary control target, thereby reducing the risk of system control failure caused by the low reliability of the sensors in the protective cabin due to long-term exposure to salt spray airflow.

[0016] The present invention also provides an anti-corrosion test method for an aviation turbojet and turbofan engine corrosion resistance test device, which is divided into four stages. The first stage is the engine running state, the second stage is the atmospheric storage state; the third stage is the salt spray storage state when the engine is not working; and the fourth stage is the wet heat storage state when the engine is not working.

[0017] The beneficial effects of the present invention are as follows:

[0018] 1. The present invention utilizes the test engine's own exhaust injection as the primary driving force for the system's air intake during engine operation, combined with exhaust fan regulation to achieve stable system air flow under different engine operating conditions. This significantly reduces the technical complexity of the air supply system caused by the high-flow air supply requirements of turbojet and turbofan engines, thereby reducing construction costs. Furthermore, through exhaust fan suction regulation, the system's total air flow remains stable under different engine operating conditions, avoiding the technical difficulty of rapidly adjusting the regulator's wide dynamic range during temperature, humidity, and salt spray simulations due to flow fluctuations, thereby ensuring control stability during the test.

[0019] 2. The present invention designs different flow paths according to the test requirements at different stages of the engine corrosion resistance test; based on the principle of minimizing simulation, different flow paths are designed for different stages of the test, and equipment selection is reasonably matched. This can reduce the construction and use costs of the system while meeting the test requirements, and improve the control accuracy of the corresponding environmental parameters of the system.

[0020] 3. The system design of the present invention controls the safety switching function; while ensuring that the environment in the protective cabin meets the test requirements, it reduces the risk of system control failure caused by the low reliability of the sensors in the protective cabin due to long-term exposure to salt spray airflow, thereby minimizing uncontrollable losses caused by system shutdown when the engine is working. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings, which constitute a part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an improper limitation of the present invention.

[0022] Figure 1 Schematic diagram of the system composition of the test device of the present invention;

[0023] Figure 2 It is a schematic diagram of the principle of the test device system of the present invention;

[0024] Figure 3 This is the schematic diagram of the salt spray injector;

[0025] Figure 4 This is the gas flow diagram for the first stage of the corrosion resistance test;

[0026] Figure 5 This is the gas flow diagram for the third stage of the corrosion resistance test;

[0027] Figure 6 This is the gas flow diagram for the fourth stage of the corrosion resistance test.

[0028] Among them: 1 air temperature regulator; 2 air intake regulating grille; 3 auxiliary air supply fan; 4 main air intake duct; 5 main air intake duct wind speed sensor; 6 main air intake duct steam injector; 7 water supply device; 8 water softener; 9 steam generator; 10 main steam pipeline electric valve; 11 gas cylinder; 12 steam regulating valve; 13 salt spray generator; 14 salt spray injector; 15 gas sampling probe; 16 salt spray absorption analysis device; 17 air duct switch valve 1; 18 exhaust fan; 19 air duct switch valve 2; 20 process air intake duct; 21 test generator Engine; 22 Salt spray protection cabin; 23 Centrifugal fan; 24 Air heater; 25 Steam injector; 26 Steam regulating valve; 27 Air conditioning unit; 28 Duct switch valve 3; 29 Duct switch valve 4; 30 Duct switch valve 5; 31 Main line humidity sensor; 32 Main line temperature sensor; 33 Temperature sensor inside protection cabin; 34 Humidity sensor inside protection cabin; 35 Wind speed sensor inside protection cabin; 36 Blind plate; 37 Exhaust pipe; 38 Spray rod; 39 Salt spray atomizing nozzle; 40 Air supply valve; 41 Liquid supply valve DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0030] This embodiment provides a corrosion resistance test device and test method for aviation turbojet and turbofan engines. The test device includes: an air intake unit, a temperature control unit, a humidity control unit, a salt spray mixing control unit, a dynamic salt spray sampling unit, a salt spray protection cabin, an air conditioning unit, an exhaust unit, and a measurement and control unit. Figure 1 shown.

[0031] The test principle is as follows Figure 2 As shown, a series of calibration tests are required before starting. First, the flow rate calibration is performed when the engine is in the maximum operating state. The specific process is as follows: close the air duct switch valve 5 30, the air duct switch valve 1 17 and the air duct switch valve 2 19, the rear of the protection cabin is in a fully open state, the engine enters the maximum thrust state, adjust the opening of the intake adjustment air grid 2, ensure that the wind speed sensor 35 in the protection cabin is within the test requirement range, record the opening k1 of the intake adjustment air grid 2, and record the measured value v5 of the main intake duct wind speed sensor 5; secondly, the salt spray generation amount calibration is performed when the engine is in the operating state. The specific process is as follows: calculate the intake flow rate q5 according to the measured value of the wind speed sensor 5, adjust the liquid supply amount qs of the salt spray generator 13 according to the intake flow rate q5, and determine the working number of the spray rod 38 according to the optimal atomization flow rate of the salt spray atomizing nozzle 39, so as to ensure that the salt spray content of the air supply meets the test requirements.

[0032] The corrosion test is divided into four stages. The first stage is the engine running state. The specific test process is as follows: In the preparation stage before the test, first close the air duct switch valve 5 30 and the air duct switch valve 2 19, and open the air duct switch valve 1 17. At this time, the main flow path of the gas is as follows: Figure 4, the external air enters the main air supply pipe 4 through the air intake tower, enters the salt spray protection cabin 22 after being regulated, and passes through the inner and outer surfaces of the test engine 21 at the same time, and finally enters the exhaust pipe 31 from the tail of the protection cabin and is discharged. Then adjust the air intake adjustment grille 2 to the calibrated opening k1 position, and choose whether to start the air temperature regulator 1 according to the ambient temperature. If the ambient temperature meets the minimum temperature required by the test, it can be disabled. If the ambient temperature is lower than the minimum temperature required by the test, the air temperature regulator 1 is turned on for preheating before the test starts, and the humidity adjustment unit is started at the same time. The water supply device 7 draws tap water from the water tower and provides it to the water softener 8 for softening treatment. Then the high-temperature steam generated by the steam generator 9 is introduced through the high-temperature steam. The total air intake speed is set to the engine's maximum operating state calibration value v5. At the beginning of the test, the engine is started, and the exhaust fan 18 is started at the same time. The exhaust fan 18 uses a variable frequency motor, and is closed-loop controlled by the difference between the measured value and v5 to ensure the engine is running smoothly. Under different thrust states of the engine, the total air intake volume of the system is stable at the air intake volume in the maximum operating state; at the same time, the air temperature regulator 1 is controlled, and feedback control is performed according to the actual measured value of the temperature sensor 33 to ensure that the value of the temperature sensor 33 is not lower than the minimum temperature required by the test; at the same time, the main steam pipeline electric valve 10 is opened, and the high-temperature steam is transported to the main intake pipeline steam injector 6 through the branch cylinder 11. Feedback control is performed on the steam regulating valve 12 according to the actual measured value of the humidity sensor 34, thereby adjusting the steam injection volume to ensure that the value of the humidity sensor 34 is not lower than the minimum humidity required by the test; at the same time, the liquid supply volume of the salt spray generator is adjusted to the calibration value qs of the maximum operating state, and the corresponding air supply valve 40 and liquid supply valve 41 are opened, as shown in FIG. Figure 3 As shown, working atomization is performed according to the predetermined working number of the spray rod 38, thereby ensuring that the salt mist content of the air supply meets the test requirements. The dynamic salt mist sampling unit provided downstream of the salt mist injector 14 extracts the pipeline sample gas through the gas sampling probe 15, and enters the salt mist absorption analysis device for salt content analysis to ensure that the salt mist content of the air supply during the test is within the test tolerance range. If the dynamic salt mist sampling unit shows an abnormal result, the working salt mist spray rod is switched to observe whether the test result returns to normal, and the test is ensured to be completed smoothly as much as possible. After the test, check whether the salt mist atomization nozzle is blocked.

[0033] The second stage is the atmospheric storage state. The entire test equipment can be shut down, and the air intake adjustment grille 2 is ensured to be fully open, and the tail of the salt spray protection cabin 22 is fully open to achieve communication between the system environment and the atmosphere.

[0034] The third stage is the salt spray storage state when the engine is not working. The specific test process is as follows: in the preparation stage before the test, first adjust the air intake adjustment grille 2 to the fully closed state, use the blind plate 36 to block the salt spray protection cabin 22, open the air duct switch valve 5 30 and the air duct switch valve 2 19, and close the air duct switch valve 1 17. At this time, the main flow path of the gas is as follows Figure 5, the indoor air passes through the auxiliary air supply fan 3 into the main air intake duct 4, and after being modulated, enters the salt spray protection cabin 22, and passes through the inner and outer surfaces of the test engine 21 at the same time, and is finally discharged to the outside through the exhaust duct at the tail end of the protection cabin via the exhaust fan 18, thereby preventing the salt spray airflow from escaping into the test room. Then the humidity adjustment unit is started, and the auxiliary air supply flow is set to the target wind speed value. At the beginning of the test, the auxiliary air supply fan 3 is started. The auxiliary air supply fan 3 uses a variable frequency motor and performs closed-loop control based on the difference between the feedback value of the main air intake duct wind speed sensor 5 and the target value to ensure that the system air supply flow is stable, and the exhaust fan controls the pumping speed according to the pressure in the protection cabin to ensure that the protection cabin is slightly negative to prevent the salt spray airflow from escaping. Since the auxiliary air supply fan draws indoor air from the test room, and the steam humidification used in the system humidification will also heat the supply air, the third stage can meet the test requirement of a temperature of not less than 10°C without additional heating. After the supply air speed stabilizes at the target value, the main steam is turned on. The pipeline electric valve 10 is used, and the opening of the steam regulating valve 12 is adjusted by closed-loop control according to the difference between the feedback value of the humidity sensor 34 and the target value, thereby adjusting the steam injection amount to ensure that the air supply humidity is stably and accurately controlled and meets the test requirements. Subsequently, the salt spray mixing adjustment unit is started, and the liquid supply volume qs1 = qs × m of the salt spray generator 13 is synchronously adjusted according to the ratio m of the third-stage system air supply volume to the first-stage system air supply volume. According to the optimal atomization flow rate of the salt spray atomizing nozzle 39, the corresponding air supply valve 40 and liquid supply valve 41 are opened to ensure that the salt spray content of the air supply meets the test requirements. The working process of the dynamic salt spray sampling unit and the control strategy for abnormal test results are consistent with those described in the first stage.

[0035] The fourth stage is the wet heat storage state when the engine is not working. The specific process is as follows: in the preparation stage before the test begins, first close the air duct switch valve 5 30, the air duct switch valve 1 17 and the air duct switch valve 2 19, ensure that the air intake adjustment grille 2 is fully closed, and the tail of the salt spray protection cabin 22 is closed. At this time, the main flow path of the gas is as follows: Figure 6 , forming a circulation loop for the air in the salt spray protection cabin 22 through the air conditioning unit 27. Subsequently, the humidity control unit is started, and the temperature target value and humidity target value are set. At the beginning of the test, the air conditioning unit 27 is started. At this time, the centrifugal fan 23 draws air from the protection cabin and sends it to the air heater 24. Closed-loop heating control is performed based on the feedback value of the cabin temperature sensor 33 to achieve precise control of the temperature in the salt spray protection cabin 22. Subsequently, the main steam pipeline electric valve 10 is opened, and closed-loop control is performed to adjust the opening of the steam regulating valve 26 based on the feedback value of the humidity sensor 34. The humidity in the salt spray protection cabin 22 is precisely controlled by adjusting the steam injection amount of the steam injector 25. Through the temperature and humidity modulation of the circulating airflow, the temperature and humidity of the environment surrounding the test engine 21 are ensured to meet the test requirements.

[0036] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A corrosion resistance test device for aviation turbojet and turbofan engines, characterized in that: include: Air intake unit, temperature control unit, humidity control unit, salt spray mixing control unit, dynamic salt spray sampling unit, salt spray protection cabin, air conditioning unit, exhaust unit and measurement and control unit; among them, The air intake unit includes an air intake duct, an air intake adjustment grille, an auxiliary air supply fan, an exhaust fan, a blind plate, and a valve. Through the adjustment of the exhaust fan and the induced ejection effect of the engine itself, a stable air supply is achieved when the engine is working. Through the coordination of the auxiliary air supply fan and the exhaust fan, the stable air supply requirement for test and assessment when the engine is not working is met. The dynamic salt spray sampling unit is used to detect and calculate the salt content in the dynamic air; The salt spray protection cabin adopts a rotating body-shaped design to wrap the test engine and process air intake; The air conditioning unit is used to simulate the high temperature and high humidity environment when the engine is stored; The exhaust unit consists of an exhaust pipe and an exhaust fan. The high-speed and high-temperature exhaust gas generated when the engine is working directly enters the exhaust pipe and is discharged after passing through the engine exhaust tower. When the engine is not working, the test gas is discharged through the exhaust fan.

2. The corrosion resistance test device for aviation turbojet and turbofan engines according to claim 1, characterized in that: The air intake unit forms different air flow paths by switching valves at different positions, thereby meeting the test air supply requirements of the engine at different stages.

3. The corrosion resistance test device for aviation turbojet and turbofan engines according to claim 1, characterized in that: The temperature regulating unit includes a heater, a temperature sensor, and a power regulator, and is used to simulate the intake ambient temperature of the engine; wherein the heater is installed in the intake tower to reduce the influence of the additional resistance of the main pipeline when the engine inhales air.

4. The corrosion resistance test device for aviation turbojet and turbofan engines according to claim 1, characterized in that: The humidity control unit includes a water supply device, a water softener, a steam generator, a gas cylinder, a steam regulating valve, and a steam injector; there are multiple steam injectors, which are respectively located at the rear end of the wind speed sensor of the main air inlet duct and the air handling unit. The steam injectors are designed with multiple steam nozzles, and the injection direction is opposite to the incoming flow direction; The salt mist mixing and adjustment unit consists of a salt mist generating device and a salt mist injection device, which is mainly used to simulate the air salt mist content in a real coastal environment; the salt mist injection device consists of multiple spray rods, and the salt mist injection direction is consistent with the incoming flow direction.

5. The corrosion resistance test device for aviation turbojet and turbofan engines according to claim 1, characterized in that: The air conditioning unit includes a centrifugal fan, an air heater and a steam injector, and adopts a skid-mounted integrated structure.

6. The corrosion resistance test device for aviation turbojet and turbofan engines according to claim 1, characterized in that: The measurement and control unit is used to control the flow path switching control and environmental parameter control of the aircraft engine corrosion resistance test device, so that the air supply volume, temperature, pressure, humidity, and salt spray concentration parameters meet the requirements of the marine environment during the engine test; at the same time, data is collected on the monitoring parameters and equipment operating status, and data storage and security protection are realized.

7. The corrosion resistance test device for aviation turbojet and turbofan engines according to any one of claims 1 to 6, characterized in that: It consists of four stages: (1) Engine running state; (2) Atmospheric storage state; (3) Salt spray storage state when the engine is not running; (4) Humid heat storage state when the engine is not running.

8. The corrosion resistance test device for aviation turbojet and turbofan engines according to claim 7, characterized in that: The specific test process for the engine running state is as follows: Preparation stage before the test begins: Control the air duct switch valve to allow external air to enter the main air supply pipe through the air intake tower. After conditioning, it enters the salt spray protection chamber and passes through the inner and outer surfaces of the test engine. Finally, it enters the exhaust pipe at the rear of the protection chamber and is discharged. Adjust the air intake control grille and choose whether to start the air temperature regulator and humidity control unit according to the ambient temperature. At the beginning of the test, the engine is started, and the exhaust fan is started at the same time, and closed-loop control is implemented to ensure that the total air intake of the system is stable at the air intake at the maximum operating state under different thrust states of the engine; at the same time, the air temperature regulator is controlled to ensure that the temperature sensor value is not lower than the minimum temperature required by the test; at the same time, feedback control is performed to adjust the steam regulating valve according to the actual measured value of the humidity sensor, thereby adjusting the steam injection amount to ensure that the humidity sensor value is not lower than the minimum humidity required by the test; at the same time, the liquid supply volume of the salt spray generator is adjusted to the calibration value qs of the maximum operating state, and the corresponding air supply valve and liquid supply valve are opened to ensure that the salt spray content of the air supply meets the test requirements, and salt content analysis is performed to ensure that the salt spray content of the air supply during the test is within the test tolerance range.

9. The corrosion resistance test according to claim 7, characterized in that: The salt spray storage state when the engine is not working is specifically: Preparation stage before the test begins: First, adjust the air intake adjustment grille to the fully closed state, use a blind plate to block the salt spray protection cabin, and control the air duct switch valve to allow indoor air to enter the main air intake duct through the auxiliary air supply fan. After conditioning, it enters the salt spray protection cabin and passes through the inner and outer surfaces of the test engine at the same time. Finally, it is discharged to the outside through the exhaust duct at the rear of the protection cabin and the exhaust fan, thereby preventing the salt spray airflow from escaping into the test room. Then start the humidity adjustment unit, set the auxiliary air supply flow rate corresponding to the wind speed target value, start the auxiliary air supply fan at the beginning of the test, and use closed-loop control to ensure the stability of the system air supply flow rate. After the air supply wind speed stabilizes at the target value, open the main steam pipeline electric valve, and adjust the steam control valve opening through closed-loop control based on the difference between the humidity sensor feedback value and the target value, thereby adjusting the steam injection amount to ensure that the air supply humidity is stably and accurately controlled and meets the test requirements. Then start the salt spray mixing adjustment unit, and adjust the liquid supply of the salt spray generator synchronously according to the ratio of the third-stage system air supply to the first-stage system air supply. According to the optimal atomization flow of the salt spray atomizing nozzle, open the corresponding air supply valve and liquid supply valve to ensure that the salt spray content of the air supply meets the test requirements.

10. The corrosion resistance test according to claim 7, characterized in that: The wet heat storage state when the engine is not working is specifically: In the preparation stage before the test begins, close the air duct switch valve, ensure that the air inlet adjustment grille is fully closed, the rear of the salt spray protection cabin is closed, and the air in the salt spray protection cabin forms a circulation loop through the air conditioning unit; Then start the humidity adjustment unit and set the temperature target value and humidity target value; At the beginning of the test, the air conditioning unit is started and closed-loop heating control is performed to achieve precise control of the temperature in the salt spray protection cabin. Then, the main steam pipeline electric valve is opened, and closed-loop control is performed to adjust the opening of the steam regulating valve according to the feedback value of the humidity sensor. The humidity in the salt spray protection cabin is precisely controlled by adjusting the steam injection amount of the steam injector. The temperature and humidity modulation of the circulating airflow ensures that the temperature and humidity of the environment surrounding the test engine meet the test requirements.

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