Regenerative cooling thrust chamber inner wall circulation heat and force impact simulation test system and method

Abstract

The invention relates to a regenerative cooling thrust chamber inner wall circulating heat and force impact simulation test system and method, which are used for solving the technical problems that an existing complete machine test run method is too high in cost and long in period, and large-scale test cannot be carried out in a thrust chamber design stage. And the deformation in the plane of the inner wall of the thrust chamber is difficult to obtain by adopting single-point temperature change measurement. According to the invention, a small modular simulation test system is adopted to replace complete machine test run, a laser heating device is adopted to replace a traditional fuel heat source, a non-contact thermal infrared camera and a DIC camera are added for measurement, and meanwhile, a measurement control module is added for feedback control. According to the invention, a low-cost and high-efficiency thrust chamber inner wall hot test run load simulation test is realized.

Description

Technical Field

[0001] This invention relates to a simulation system and method for a regenerative cooling thrust chamber, specifically to a simulation test system and method for cyclic thermal and mechanical impact on the inner wall of a regenerative cooling thrust chamber. Background Technology

[0002] Currently, many types of engines face the challenge of reusability, and the regenerative cooling thrust chamber is a key component of reusable liquid rocket engines. The operating environment and loads of the regenerative cooling thrust chamber are quite harsh, and its failure directly determines the engine's service life. Significant temperature gradients and pressure differential loads exist on both sides of the thrust chamber's inner wall. During repeated restarts, the inner wall gradually bulges towards the combustion gas side and eventually fractures. Thrust chamber inner wall failure is a bottleneck problem in the development of reusable engines, requiring accurate experimental evaluation techniques to identify its key sensitive factors to guide structural life determination and optimization for life extension.

[0003] Currently, there are three main methods for assessing the reusability of regenerative cooling thrust chambers:

[0004] 1) Material-level fatigue life testing has the disadvantage that there is a large difference between material-level testing and actual structural loads, resulting in insufficient evaluation accuracy.

[0005] 2) The disadvantage of the cyclic pressure test of the inner wall of the thrust chamber is that a uniform pressure field is applied by high-pressure water in the inner wall of the thrust chamber. On the one hand, it is impossible to accurately control the flow and pressure in each cooling channel, and on the other hand, it is impossible to consider the cooling temperature. Moreover, it only has pressure load and cannot consider the thermal shock load borne by the inner wall.

[0006] 3) Engine testing: Currently, the heat source for engine testing is the heat released from the combustion of fuel and oxidizer, with a heat flux density reaching 80 MW / m³. 2 However, its disadvantages include high cost and long cycle time, making large-scale testing impossible during the design phase of the regenerative cooling thrust chamber. In other thermal tests using test specimens, quartz lamp heating is commonly used, but its heat flux density is far lower than the requirements of actual test runs.

[0007] In addition, the measurement of temperature and deformation fields is quite difficult in the currently commonly used hot-running tests due to the limitations of the engine mechanism. For the temperature field, thermocouples are generally used to measure the temperature change at a single point; for the displacement field, usually only the normal displacement change of the inner wall surface (surface morphology) before and after the test can be obtained, but the deformation in the inner wall plane cannot be obtained. Summary of the Invention

[0008] The purpose of this invention is to solve the technical problems of existing whole-machine testing methods being too costly and time-consuming, making it impossible to conduct large-scale tests during the design phase of the regenerative cooling thrust chamber, as well as the technical problems of using single-point temperature measurement and difficulty in obtaining in-plane deformation of the inner wall of the thrust chamber in existing hot test. The invention proposes a cyclic thermal and force impact simulation test system and method for the inner wall of the regenerative cooling thrust chamber.

[0009] To solve the above-mentioned technical problems, the technical solution provided by the present invention is as follows:

[0010] A regenerative cooling thrust chamber wall circulating thermal and force impact simulation test system is characterized by including a fixed module, and a liquid flow cooling unit, a liquid flow control unit, a laser heat transfer unit, a measurement control unit, and a test piece mounted on the fixed module;

[0011] The fixed module includes a platform and a support frame erected vertically on the platform; the platform has a mounting slot in the middle for mounting the test piece; the test piece has a cooling channel inside, as well as a cooling slot consistent with that in the thrust chamber.

[0012] The liquid flow cooling unit includes an input pipeline, an output pipeline, a coolant tank, and a recovery system; one end of the input pipeline is connected to the coolant tank, and the other end is connected to the input end of the cooling channel; one end of the output pipeline is connected to the recovery system, and the other end is connected to the output end of the cooling channel.

[0013] The fluid flow control unit includes a control valve installed on the input pipeline and a fluid flow control module connected to the control valve; the fluid flow control module is used to regulate the pressure and flow rate of the control valve.

[0014] The laser heat transfer unit includes a laser heating device and a laser heat flow controller; the laser heating device is adjustablely mounted on the support frame and located above the mounting slot; the laser heat flow controller is connected to the laser heating device and is used to control the power of the laser heating device.

[0015] The measurement and control unit includes a measurement and control module, as well as an adjustable thermal infrared camera and a DIC camera mounted on the support frame and located above the mounting slot side; the measurement and control module is connected to the thermal infrared camera and the DIC camera, and is used to receive the test piece surface temperature data measured in real time by the thermal infrared camera and the test piece surface image data captured in real time by the DIC camera.

[0016] Furthermore, the liquid flow cooling unit also includes an input interface and an output interface; the input interface and the output interface are respectively installed on the inner walls of opposite sides of the mounting groove, and are respectively connected to the input end and the output end of the cooling flow channel of the test piece; the other end of the input pipe is connected to the input interface, and the other end of the output pipe is connected to the output interface.

[0017] Furthermore, it also includes a first fixed clamp, a second fixed clamp, and a third fixed clamp with the same structure, each including a fixed ring, a telescopic arm, and a movable ring; the fixed ring is sleeved on the side of the support frame and locked by screws; one end of the telescopic arm is fixedly connected to the fixed ring, and the other end is movably connected to the movable ring;

[0018] The fixing rings of the first fixing clamp and the second fixing clamp are fitted onto the same side of the support frame, and the DIC camera and the thermal infrared camera are respectively installed in the movable rings of the first fixing clamp and the second fixing clamp.

[0019] The fixing ring of the third fixing clamp is sleeved on the other side of the support frame, and the laser heating device is installed in the movable ring of the third fixing clamp.

[0020] Furthermore, the recovery system is a kerosene storage tank, which uses high-pressure kerosene for recovery.

[0021] A method for simulating the cyclic thermal and force impact of a regenerative cooling thrust chamber wall, based on the aforementioned simulation test system for cyclic thermal and force impact of a regenerative cooling thrust chamber wall, is characterized by including the following steps:

[0022] 1) Establish the pressure and temperature load curves at the throat of the thrust chamber:

[0023] 1.1) Determine the chamber pressure, combustion gas temperature, and coolant flow rate, temperature, and pressure parameters of the thrust chamber under the engine's start-up, stable, and shutdown conditions, based on the engine design requirements;

[0024] 1.2) Extract the chamber pressure, gas temperature, coolant flow rate, temperature, and pressure parameters of the thrust chamber under the corresponding operating conditions during the actual test run;

[0025] 1.3) Perform one-dimensional fluid-heat transfer analysis on the two sets of parameters in steps 1.1 and 1.2 to obtain the pressure load curve and temperature load curve of the thrust chamber throat;

[0026] 2) Three measuring points S1, S2 and S3 are evenly arranged along the length of the cooling channel of the test piece, and pressure sensors and temperature sensors are installed on measuring points S1, S2 and S3; the test piece is calibrated by liquid flow cooling test and laser heat flow test, and the calibration curves of the temperature and pressure of the coolant and the calibration curve of the laser heating device are obtained respectively.

[0027] 3) Spray speckle on the upper surface of the test piece, which is used to detect the surface deformation of the test piece by real-time image data of the test piece surface captured by the DIC camera; start the measurement control unit to ensure that the thermal infrared camera can perform temperature detection and the DIC camera can perform surface deformation detection normally.

[0028] 4) Based on the thrust chamber throat pressure and temperature load curve established in step 1, and the coolant temperature and pressure calibration curve and laser heating device calibration curve obtained in step 2, compare the temperature and pressure data one by one to obtain the predetermined control parameters of coolant and laser heating device under various engine operating conditions.

[0029] 5) Conduct thermal shock simulation tests;

[0030] 5.1) Turn on the liquid cooling unit and ensure that the temperature and pressure data on measuring points S1, S2 and S3 are displayed normally, and that there are no leaks in the test piece, input pipeline and output pipeline.

[0031] 5.2) Turn off the liquid cooling unit and wait for the platform and test piece to return to room temperature;

[0032] 5.3) Simultaneously activate the liquid cooling unit and the laser heat transfer unit, and generate a thermo-mechanical impact load according to the predetermined control parameters to complete the simulation of the engine starting process; record the temperature and pressure at each measuring point in real time during the process, and record the surface temperature change and surface deformation of the test piece through a thermal infrared camera and a DIC camera;

[0033] 5.4) Keep the liquid cooling unit running. The laser heat flow controller adjusts the power of the laser heating device according to the predetermined control parameters to keep the temperature of the inner wall of the test piece at the temperature when the engine is running stably, simulating the stable operation process of the engine. Record the temperature and pressure of each measuring point in real time during this process, and record the surface temperature change and surface deformation of the test piece through the thermal infrared camera and DIC camera.

[0034] 5.5) According to the predetermined control parameters, shut down the liquid cooling unit and the laser heat transfer unit to simulate the engine shutdown process; record the temperature and pressure at each measuring point in real time during this process until the test piece returns to room temperature;

[0035] 5.6) Repeat steps 5.3, 5.4 and 5.5 until any termination condition is met to complete the cyclic thermal shock test;

[0036] The termination conditions are determined as follows:

[0037] a. The surface deformation of the test specimen exceeds the predetermined limit value;

[0038] b. Cracks appear on the surface of the test piece and the crack length exceeds the predetermined limit value;

[0039] c. The cooling tank structure of the test piece is severely deformed, causing the temperature of the coolant or the surface of the test piece to exceed the predetermined limit.

[0040] d. The number of repetitions of step 6.6 exceeds the predetermined limit;

[0041] e. An anomaly occurs in the simulation test system, wherein the anomaly refers to the test piece cracking, causing the coolant pressure to deviate from the design value, or a malfunction in the simulation test system.

[0042] Furthermore, the liquid flow cooling test calibration in step 2 specifically includes:

[0043] A.1) Open the coolant tank and let the coolant flow through the cooling channel of the test piece; the pressure and temperature sensors at measuring points S1, S2 and S3 collect pressure and temperature data and feed them back to the liquid flow control module in real time.

[0044] A.2) The fluid flow control module regulates the control valve through the PID control algorithm, optimizes the pressure and flow parameters of the control valve, and makes the measured temperature and pressure of the test piece in the test calibration consistent with the actual load in the regenerative cooling thrust chamber, so as to obtain the temperature and pressure calibration curves of the coolant in the steady state and the changing state.

[0045] Furthermore, the laser thermal flux test calibration in step 2 specifically includes:

[0046] B.1) Turn on the laser heating device to heat the test piece. The pressure and temperature sensors at measuring points S1, S2 and S3 collect pressure and temperature data and transmit them to the laser heat flow controller.

[0047] B.2) The laser heat flow controller performs heat transfer calculations to obtain data on the temperature change of the test specimen wall surface;

[0048] B.3) Based on the change data of the wall temperature, adjust the position and angle of the laser heating device, optimize and adjust the spot size and heat flux density parameters, and obtain the calibration curve of the laser heating device in steady state and changing state when the measured temperature and pressure of the test piece in the test calibration are consistent with the actual load in the regenerative cooling thrust chamber.

[0049] Furthermore, it also includes step 6:

[0050] 6) Disassemble the test piece and clean the simulation test system. Measure and microscopically characterize the test piece after the test. Establish a simulation model consistent with the test piece before the test. Based on predetermined control parameters, simulate the fluid-solid heat transfer process of the test piece to verify whether the inner wall temperature of the test piece in the simulation test method for the cyclic thermal and force impact of the inner wall of the regenerative cooling thrust chamber meets the test design requirements. Based on predetermined control parameters, simulate the thermal-solid coupling deformation process of the test piece and compare it with the surface deformation of the test piece in step 5 to verify whether the simulation test method for the cyclic thermal and force impact of the inner wall of the regenerative cooling thrust chamber meets the test design requirements.

[0051] Compared with the prior art, the beneficial effects of the present invention are:

[0052] 1. This invention relates to a regenerative cooling thrust chamber inner wall circulating thermal and force impact simulation test system. It employs a small, modular simulation test system instead of a full-engine test, uses a laser heating device instead of a traditional fuel heat source, and adds non-contact thermal infrared cameras and DIC cameras for measurement. It also includes a measurement control module for feedback control. This invention achieves low-cost, high-efficiency thrust chamber inner wall thermal test load simulation.

[0053] 2. The regenerative cooling thrust chamber wall circulating thermal and force impact simulation test system of the present invention can realize high-power heat flow input, cooling heat exchange, and precise feedback control of mechanical load application to simulate the thermal and force impact state of real test, and measure temperature, pressure and deformation field in real time.

[0054] 3. The regenerative cooling thrust chamber wall circulating thermal and force impact simulation test system of the present invention has an input interface and an output interface designed in the liquid flow cooling unit, which makes the test system have the characteristics of high reliability, high compatibility, high scalability, low cost and easy operation.

[0055] 4. The regenerative cooling thrust chamber inner wall circulating thermal and force impact simulation test method of the present invention uses a liquid flow control unit to precisely adjust the pressure and temperature of the cooling channel of the test piece to simulate the load environment consistent with the actual test. The present invention uses non-contact measurement methods to measure the temperature and displacement changes of the test piece in real time during the test, and verifies and calibrates through fluid-thermal-solid coupling calculation.

[0056] 5. The present invention provides a method for simulating the cyclic thermal and mechanical shock of the inner wall of the regenerative cooling thrust chamber. Based on engine design requirements and thrust chamber whole-machine test measurement data, it establishes the thrust chamber throat pressure and temperature load curves during the repeated use of the engine; through calibration tests and thrust chamber throat pressure and temperature load curves, it determines the predetermined control parameters of the coolant and laser heating device; and conducts cyclic thermal-mechanical shock simulation tests according to the predetermined control parameters until the termination conditions are met, thus completing the cycle.

[0057] 6. The present invention provides a simulation test method for the circulating thermal and force impact of the inner wall of the regenerative cooling thrust chamber. A simulation model consistent with the test specimen before the test is established. Based on the temperature, pressure and measurement data, the fluid-solid heat transfer process and the thermal-solid coupling deformation process of the test specimen are simulated, and the effectiveness of the simulation test method is verified by comparison. Attached Figure Description

[0058] Figure 1 This is a schematic diagram of an embodiment of the regenerative cooling thrust chamber wall circulating thermal and mechanical impact simulation test system of the present invention;

[0059] Figure 2 The thrust chamber throat pressure and temperature load curves are shown in the embodiment of the regenerative cooling thrust chamber inner wall circulating thermal and mechanical impact simulation test method of the present invention.

[0060] Figure 3 This is a schematic diagram of the test specimen in an embodiment of the regenerative cooling thrust chamber wall circulating thermal and mechanical impact simulation test system of the present invention;

[0061] Figure 4 This is a schematic diagram of the measuring points of the test piece in an embodiment of the regenerative cooling thrust chamber wall circulating thermal and mechanical impact simulation test system of the present invention.

[0062] Figure 5 This is a schematic diagram of speckle spraying and a DIC camera in an embodiment of the regenerative cooling thrust chamber wall circulating thermal and force impact simulation test method of the present invention.

[0063] Explanation of reference numerals in the attached figures:

[0064] 1-Support frame; 2-Platform; 3-Test piece; 31-Cooling channel; 41-Input interface; 42-Output interface; 5-Input pipeline; 6-Control valve; 7-Coolant tank; 8-Output pipeline; 9-Recovery system; 10-First fixed clamp; 11-Second fixed clamp; 12-DIC camera; 13-Thermal infrared camera; 14-Third fixed clamp; 16-Fluid flow control module; 17-Measurement control module; 18-Laser heat flow controller; 19-Laser heating device. Detailed Implementation

[0065] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0066] This invention provides a simulation test system for the circulating thermal and mechanical impact of a regenerative cooling thrust chamber wall, such as... Figure 1 As shown, it includes a fixed module, as well as a liquid cooling unit, a liquid control unit, a laser heat transfer unit, a measurement control unit, and a test piece 3 mounted on the fixed module.

[0067] The fixed module includes a support frame 1 and a platform 2. The support frame 1 is vertically erected on the platform 2. A mounting slot is provided in the middle of the platform 2 for mounting the test specimen 3 required for the simulation experiment. Figure 3 As shown, the test piece 3 has a cooling channel 31 inside, as well as a cooling tank consistent with that in the thrust chamber;

[0068] The liquid flow cooling unit includes an input pipe 5, an output pipe 8, an input interface 41, an output interface 42, a coolant tank 7, and a recovery system 9. One end of the input pipe 5 is connected to the coolant tank 7, which provides a constant-temperature coolant. The other end of the input pipe 5 is connected to the input interface 41. The input interface 41 is installed on the inner wall of one side of the mounting slot and is used to connect with the input end of the cooling channel 31. One end of the output pipe 8 is connected to the recovery system 9, and the other end is connected to the output interface 42. The output interface 42 is located on the inner wall of the other side of the mounting slot and is opposite to the input interface 41, used to connect with the output end of the cooling channel 31. The recovery system 9 is selected according to the type of coolant; in this embodiment, high-pressure kerosene is used for recovery. The recovery system 9 is a kerosene tank.

[0069] The fluid flow control unit includes a control valve 6 and a fluid flow control module 16; the control valve 6 is installed on the input pipeline 5 and connected to the fluid flow control module 16; the fluid flow control module 16 is used to regulate the pressure and flow rate of the control valve 6.

[0070] The measurement control unit includes a DIC camera 12, a thermal infrared camera 13, and a measurement control module 17.

[0071] The DIC camera 12 is mounted on the support frame 1 via an adjustable first fixing clamp 10, located above and to the side of the mounting slot. The first fixing clamp 10 includes a fixing ring, a telescopic arm, and a movable ring. The fixing ring is fitted onto one side of the support frame 1 and, after being adjusted to a suitable mounting height, is locked with screws. One end of the telescopic arm is fixedly connected to the fixing ring, and the other end is movably connected to the movable ring. The DIC camera 12 is mounted in the movable ring. By adjusting the height of the fixing ring, the length of the telescopic arm, and the angle of the movable ring, the DIC camera 12 can capture images of the surface of the test piece 3 in the mounting slot.

[0072] The thermal infrared camera 13 is mounted on the support frame 1 via an adjustable second fixing clamp 11, located above and to the side of the mounting slot. The second fixing clamp 11 has the same structure as the first fixing clamp 10, with its fixing ring sleeved on one side of the support frame 1 and positioned above the fixing ring of the first fixing clamp 10. The thermal infrared camera 13 is mounted in the movable ring of the second fixing clamp 11, allowing for height and shooting angle adjustment to ensure that the thermal infrared camera 13 can collect the temperature of the surface of the test piece 3 in the mounting slot.

[0073] The measurement control module 17 connects to the thermal infrared camera 13 and the DIC camera 12, and is used to receive the surface temperature data of the test piece 3 measured in real time by the thermal infrared camera 13 and the surface image data of the test piece 3 captured in real time by the DIC camera 12. A speckle pattern is sprayed onto the upper surface of the test piece 3, and the surface deformation of the test piece 3 is calculated by comparing the changes in the speckle pattern in the surface image data of the test piece 3 captured in real time by the DIC camera 12.

[0074] The laser heat carrier unit includes a laser heating device 19 and a laser heat flow controller 18. The laser heating device 19 is mounted on the support frame 1 via an adjustable third fixing clamp 14, and is located above the mounting groove. The third fixing clamp 14 has the same structure as the first fixing clamp 10. The fixing ring of the third fixing clamp 14 is sleeved on the other side of the support frame 1, and the laser heating device 19 is installed in the movable ring of the third fixing clamp 14, allowing for adjustment of its height and irradiation angle. The laser heat flow controller 18 is connected to the laser heating device 19 and is used to control the power of the laser heating device 19.

[0075] This invention also provides a method for simulating the thermal and mechanical impact of regenerative cooling thrust chamber wall circulation.

[0076] 1) Establish the pressure and temperature load curves at the throat of the thrust chamber:

[0077] 1.1) Determine the chamber pressure, combustion gas temperature, and coolant flow rate, temperature, and pressure parameters of the regenerative cooling thrust chamber under engine start-up, stable operation, and shutdown conditions according to engine design requirements;

[0078] 1.2) Extract the chamber pressure, gas temperature, coolant flow rate, temperature and pressure parameters of the regenerative cooling thrust chamber under the corresponding operating conditions during the actual test run;

[0079] 1.3) As Figure 2 As shown, a one-dimensional fluid-heat transfer analysis was performed on the two sets of parameters in steps 1.1 and 1.2 to obtain the pressure load curve and temperature load curve of the thrust chamber throat.

[0080] 2) Three measuring points S1, S2 and S3 are evenly arranged along the length of the cooling channel 31 of the test piece 3, and pressure sensors and temperature sensors are installed at S1, S2 and S3 respectively; liquid flow cooling test calibration and laser heat flow test calibration are performed on the test piece 3 to obtain the calibration curves of the temperature and pressure of the coolant and the calibration curve of the laser heating device 19 respectively; in the test of the simulation test system, due to the influence of factors such as the absorption rate of the test piece 3, there is a gap between the actual output pressure and temperature load curves of the coolant and the laser heating device 19 and the pressure and temperature load curves of the thrust chamber throat in step 1. Therefore, it is necessary to first test and calibrate the liquid flow cooling of the coolant and the laser heating of the laser heating device 19.

[0081] The specific calibration of the liquid flow cooling test includes:

[0082] A) such as Figure 4 As shown, open coolant tank 7 and calibrate the temperature and pressure of the coolant to obtain a temperature and pressure calibration curve for the coolant; specifically:

[0083] A.1) Open the coolant tank 7, and the coolant flows through the cooling channel 31 of the test piece 3; the pressure and temperature sensors at measuring points S1, S2 and S3 collect pressure and temperature data and feed them back to the liquid flow control module 16 in real time.

[0084] A.2) The fluid flow control module 16 regulates the control valve 6 through the PID control algorithm, optimizes the pressure and flow parameters of the control valve 6, and makes the measured temperature and pressure of the test piece 3 in the test calibration consistent with the actual load in the regenerative cooling thrust chamber, so as to obtain the temperature and pressure calibration curves of the coolant in the steady state and the changing state process.

[0085] Laser thermal flow test calibration specifically includes:

[0086] B) Turn on the laser heating device 19 and calibrate its temperature and pressure to obtain a calibration curve for the laser heating device 19; specifically:

[0087] B.1) Turn on the laser heating device 19 to heat the test piece 3. The pressure and temperature sensors on the measuring points S1, S2 and S3 collect pressure and temperature data and transmit them to the laser heat flow controller 18.

[0088] B.2) The laser heat flow controller 18 performs heat transfer calculations to obtain the temperature change data of the test piece 3 wall surface;

[0089] B.3) Based on the change data of the wall temperature, adjust the position and angle of the laser heating device 19, optimize and adjust parameters such as spot size and heat flux density, and obtain the calibration curves of the laser heating device 19 in steady state and changing state when the measured temperature and pressure of the test piece 3 in the test calibration are consistent with the actual load in the regenerative cooling thrust chamber.

[0090] 3) such as Figure 5 As shown, speckle pattern is sprayed onto the upper surface of test piece 3, the measurement control unit is activated, and the thermal infrared camera 13 is used to detect temperature and the DIC camera 12 is used to detect surface deformation.

[0091] 4) Based on the thrust chamber throat pressure and temperature load curve established in step 1, and the coolant temperature and pressure calibration curve and laser heating device 19 calibration curve obtained in step 2, the temperature and pressure data are matched one by one to obtain the predetermined control parameters of coolant and laser heating device 19 under various engine operating conditions.

[0092] 5) Conduct thermal shock simulation tests;

[0093] 5.1) Turn on the liquid cooling unit to ensure that the temperature and pressure data at measuring points S1, S2, and S3 are displayed normally, and that there are no leaks in test piece 3, input pipe 5, and output pipe 8; specifically:

[0094] Turn on the liquid cooling unit. The coolant flows from the coolant tank 7 through the test piece 3 to the recovery system 9. Monitor whether the temperature and pressure data at measuring points S1, S2, and S3 are displayed normally. If they are not displayed normally, return to step 2 and rearrange the measuring points until the temperature and pressure data at measuring points S1, S2, and S3 are all displayed normally. Check whether there is any leakage in the test piece 3, input pipe 5, and output pipe 8 during the coolant flow. If there is, replace the leaking parts and check again until there is no leakage in the test piece 3, input pipe 5, and output pipe 8.

[0095] 5.2) Turn off the liquid cooling unit and wait for platform 2 and test piece 3 to return to room temperature;

[0096] 5.3) Simultaneously activate the liquid cooling unit and the laser heat transfer unit, generate a thermal-mechanical impact load according to the predetermined control parameters obtained in step 4, and complete the simulation of the engine starting process; record the temperature and pressure at each measuring point in real time during the process, and record the surface temperature change and surface deformation of the test piece 3 through the thermal infrared camera 13 and the DIC camera 12 respectively.

[0097] 5.4) Keep the liquid cooling unit running. The laser heat flow controller 18 adjusts the power of the laser heating device 19 according to the predetermined control parameters so that the temperature of the inner wall of the test piece 3 is maintained at the temperature when the engine is working stably, simulating the engine working stably. The temperature and pressure of each measuring point are recorded in real time during this process, and the surface temperature change and surface deformation of the test piece 3 are recorded by the thermal infrared camera and the DIC camera 12 respectively.

[0098] 5.5) According to the predetermined control parameters, shut down the liquid cooling unit and the laser heat transfer unit to simulate the engine shutdown process; record the temperature and pressure at each measuring point in real time during this process until the test piece 3 returns to room temperature;

[0099] 5.6) Repeat steps 5.3, 5.4 and 5.5 until any termination condition is met to complete the cyclic thermo-shock simulation test;

[0100] The termination conditions are as follows:

[0101] a. The surface deformation of test piece 3 exceeds the predetermined limit value;

[0102] b. Cracks appear on the surface of test piece 3 and the crack length exceeds the predetermined limit value;

[0103] c. The cooling tank structure of test piece 3 is severely deformed, causing the temperature of the coolant or the surface of test piece 3 to exceed the predetermined limit.

[0104] d. The number of repetitions in step 5.6 exceeds the predetermined limit;

[0105] e. An anomaly occurs in the simulation test system. An anomaly refers to a deviation of the coolant pressure from the design value due to cracking of the test piece, or a malfunction in the simulation test system.

[0106] 6) Disassemble test piece 3 and clean the simulation test system. Perform measurements and microscopic characterization on test piece 3 after the test.

[0107] A simulation model consistent with the test specimen 3 before the experiment was established. According to the predetermined control parameters, the fluid-solid heat transfer process of test specimen 3 was simulated to verify whether the inner wall temperature of test specimen 3 in the simulation test method of cyclic thermal and force impact of regenerative cooling thrust chamber wall met the experimental design requirements. According to the predetermined control parameters, the thermal-solid coupling deformation process of test specimen 3 was simulated and compared with the deformation of test specimen 3 in step 5 to verify whether the inner wall deformation of test specimen 3 in the simulation test method of cyclic thermal and force impact of regenerative cooling thrust chamber wall met the experimental design requirements.

Claims

1. A simulation test system for circulating thermal and mechanical shock of the inner wall of a regenerative cooling thrust chamber, characterized in that: It includes a fixed module, as well as a liquid cooling unit, a liquid control unit, a laser heat transfer unit, a measurement control unit and a test piece (3) mounted on the fixed module; The fixed module includes a platform (2) and a support frame (1) erected vertically on the platform (2); the platform (2) has an installation groove in the middle for installing the test piece (3); the test piece (3) has a cooling channel (31) inside and a cooling groove consistent with that in the thrust chamber; The liquid flow cooling unit includes an input pipe (5), an output pipe (8), a coolant tank (7), and a recovery system (9); one end of the input pipe (5) is connected to the coolant tank (7), and the other end is connected to the input end of the cooling channel (31); one end of the output pipe (8) is connected to the recovery system (9), and the other end is connected to the output end of the cooling channel (31); The fluid flow control unit includes a control valve (6) installed on the input pipeline (5) and a fluid flow control module (16) connected to the control valve (6); the fluid flow control module (16) is used to regulate the pressure and flow rate of the control valve (6); The laser heat transfer unit includes a laser heating device (19) and a laser heat flow controller (18); the laser heating device (19) is adjustablely mounted on the support frame (1) and located above the mounting slot; the laser heat flow controller (18) is connected to the laser heating device (19) and is used to control the power of the laser heating device (19); The measurement control unit includes a measurement control module (17), and an adjustable thermal infrared camera (13) and a DIC camera (12) mounted on the support frame (1) and located above the mounting slot side; the measurement control module (17) is connected to the thermal infrared camera (13) and the DIC camera (12) and is used to receive the surface temperature data of the test piece (3) measured in real time by the thermal infrared camera (13) and the surface image data of the test piece (3) captured in real time by the DIC camera (12).

2. The regenerative cooling thrust chamber wall circulating thermal and mechanical impact simulation test system according to claim 1, characterized in that: The liquid flow cooling unit also includes an input interface (41) and an output interface (42); the input interface (41) and the output interface (42) are respectively installed on the inner walls of opposite sides of the mounting slot and are respectively connected to the input end and the output end of the cooling channel (31) of the test piece (3); the other end of the input pipe (5) is connected to the input interface (41) and the other end of the output pipe (8) is connected to the output interface (42).

3. The regenerative cooling thrust chamber wall circulating thermal and mechanical shock simulation test system according to claim 2, characterized in that: It also includes a first fixed clamp (10), a second fixed clamp (11) and a third fixed clamp (14) with the same structure, each including a fixed ring, a telescopic arm and a movable ring; the fixed ring is sleeved on the side of the support frame (1) and locked by screws; one end of the telescopic arm is fixedly connected to the fixed ring and the other end is movably connected to the movable ring; The fixing rings of the first fixing clamp (10) and the second fixing clamp (11) are fitted on the same side of the support frame (1), and the DIC camera (12) and the thermal infrared camera (13) are respectively installed in the movable rings of the first fixing clamp (10) and the second fixing clamp (11). The fixing ring of the third fixing clamp (14) is sleeved on the other side of the support frame (1), and the laser heating device (19) is installed in the movable ring of the third fixing clamp (14).

4. The regenerative cooling thrust chamber wall circulating thermal and mechanical shock simulation test system according to claim 3, characterized in that: The recovery system (9) is a kerosene storage tank, which uses high-pressure kerosene for recovery.

5. A method for simulating the cyclic thermal and force impact of a regenerative cooling thrust chamber wall, based on the cyclic thermal and force impact simulation test system for a regenerative cooling thrust chamber wall as described in claims 1-4, characterized in that, Includes the following steps: 1) Establish the pressure and temperature load curves at the throat of the thrust chamber: 1.1) Determine the chamber pressure, combustion gas temperature, and coolant flow rate, temperature, and pressure parameters of the thrust chamber under the engine's start-up, stable, and shutdown conditions, based on the engine design requirements; 1.2) Extract the chamber pressure, gas temperature, coolant flow rate, temperature, and pressure parameters of the thrust chamber under the corresponding operating conditions during the actual test run; 1.3) Perform one-dimensional fluid-heat transfer analysis on the two sets of parameters in steps 1.1 and 1.2 to obtain the pressure load curve and temperature load curve of the thrust chamber throat; 2) Three measuring points S1, S2 and S3 are evenly arranged along the length of the cooling channel (31) of the test piece (3), and pressure sensors and temperature sensors are installed on measuring points S1, S2 and S3 (no need to repeat so many times); liquid flow cooling test calibration and laser heat flow test calibration are performed on the test piece (3), and the calibration curves of the temperature and pressure of the coolant and the calibration curve of the laser heating device (19) are obtained respectively. 3) Spray speckle on the upper surface of the test piece (3) to detect the surface deformation of the test piece (3) using the surface image data of the test piece (3) captured in real time by the DIC camera (12); Start the measurement control unit to ensure that the thermal infrared camera (13) performs temperature detection normally and the DIC camera (12) performs surface deformation detection normally; 4) Based on the thrust chamber throat pressure and temperature load curve established in step 1, and the coolant temperature and pressure calibration curve and laser heating device (19) calibration curve obtained in step 2, compare the temperature and pressure data one by one to obtain the predetermined control parameters of coolant and laser heating device (19) under various engine operating conditions. 5) Conduct thermal shock simulation tests; 5.1) Turn on the liquid cooling unit to ensure that the temperature and pressure data on the measuring points S1, S2 and S3 are displayed normally, and that there is no leakage in the test piece (3), the input pipeline (5) and the output pipeline (8); 5.2) Turn off the liquid cooling unit and wait for the platform (2) and test piece (3) to return to room temperature; 5.3) Simultaneously turn on the liquid flow cooling unit and the laser heat load unit, generate thermal-mechanical impact load according to the predetermined control parameters, and complete the simulation of the engine start-up process; record the temperature and pressure of each measuring point in real time during the process, and record the surface temperature change and surface deformation of the test piece (3) through the thermal infrared camera and DIC camera (12); 5.4) Keep the liquid cooling unit running, and the laser heat flow controller (18) adjusts the power of the laser heating device (19) according to the predetermined control parameters so that the temperature of the inner wall of the test piece (3) is maintained at the temperature when the engine is working stably, simulating the engine working stably; record the temperature and pressure of each measuring point in real time during this process, and record the surface temperature change and surface deformation of the test piece (3) through the thermal infrared camera and DIC camera (12); 5.5) According to the predetermined control parameters, shut down the liquid cooling unit and the laser heat transfer unit to simulate the engine shutdown process; record the temperature and pressure at each measuring point in real time during the process until the test piece (3) returns to room temperature; 5.6) Repeat steps 5.3, 5.4 and 5.5 until any termination condition is met to complete the cyclic thermal shock test; The termination conditions are determined as follows: a. The surface deformation of the test specimen (3) exceeds the predetermined limit value; b. Cracks appear on the surface of the test piece (3) and the crack length exceeds the predetermined limit value; c. The cooling tank structure of the test piece (3) is severely deformed, causing the temperature of the coolant or the surface of the test piece (3) to exceed the predetermined limit. d. The number of repetitions of step 6.6 exceeds the predetermined limit; e. An abnormality occurs in the simulation test system, the abnormality being that the test piece (3) cracks, causing the coolant pressure to deviate from the design value, or a malfunction occurs in the simulation test system.

6. The method for simulating the thermal and mechanical impact of the regenerative cooling thrust chamber wall according to claim 5, characterized in that, The liquid flow cooling test calibration in step 2 specifically includes: A.1) Open the coolant tank (7), and the coolant flows through the cooling channel (31) of the test piece (3); the pressure sensor and temperature sensor on the measuring points S1, S2 and S3 collect pressure and temperature data and feed them back to the liquid flow control module (16) in real time. A.2) The liquid flow control module (16) regulates the control valve (6) through the PID control algorithm, optimizes the pressure and flow parameters of the control valve (6), and makes the measured temperature and pressure of the test piece (3) in the test calibration consistent with the actual load in the regenerative cooling thrust chamber, so as to obtain the temperature and pressure calibration curves of the coolant in the steady state and the changing state process.

7. The method for simulating the thermal and mechanical impact of the regenerative cooling thrust chamber wall according to claim 6, characterized in that, The laser thermal flow test calibration in step 2 specifically includes: B.1) Turn on the laser heating device (19) to heat the test piece (3). The pressure and temperature sensors on the measuring points S1, S2 and S3 collect pressure and temperature data and transmit them to the laser heat flow controller (18). B.2) The laser heat flow controller (18) performs heat transfer calculations and obtains the temperature change data of the test piece (3) wall surface; B.3) Based on the change data of the wall temperature, adjust the position and angle of the laser heating device (19), optimize and adjust the spot size and heat flux density parameters, and obtain the calibration curve of the laser heating device (19) in steady state and changing state when the measured temperature and pressure of the test piece (3) in the test calibration are consistent with the actual load in the regenerative cooling thrust chamber.

8. The method for simulating the thermal and mechanical impact of the regenerative cooling thrust chamber wall according to claim 7, characterized in that, It also includes step 6: 6) Disassemble the test piece (3) and clean the simulation test system. Measure and microscopically characterize the test piece (3) after the test. Establish a simulation model consistent with the test piece (3) before the test. Simulate the fluid-solid heat transfer process of the test piece (3) according to the predetermined control parameters. Verify whether the inner wall temperature of the test piece (3) in the regenerative cooling thrust chamber wall circulating thermal and force impact simulation test method meets the test design requirements. Simulate the thermal-solid coupling deformation process of the test piece (3) according to the predetermined control parameters. Compare it with the surface deformation of the test piece (3) in step 5 to verify whether the regenerative cooling thrust chamber wall circulating thermal and force impact simulation test method meets the test design requirements.

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