Methods, systems, equipment, and media for determining the loading temperature in cylinder head thermal fatigue testing

Abstract

This application provides a method, system, equipment, and medium for determining the loading temperature of a cylinder head thermal fatigue test. By performing a whole-engine temperature measurement test on the cylinder head mounted on the engine, and a temperature measurement test on the cylinder head mounted on a thermal fatigue testing device, the minimum low-cycle fatigue life of the cylinder head under engine operating conditions is compared with the low-cycle fatigue life of the cylinder head at the corresponding low-cycle fatigue danger point location in the thermal fatigue test. Based on the deviation comparison result, the loading temperature of the low-cycle fatigue danger point in the cylinder head thermal fatigue test is determined. This application compensates for the differences in thermal damage in the heatsink area caused by the different cooling methods and cooling rates of the cylinder head in the thermal fatigue testing device and engine bench by optimizing the loading temperature of the cylinder head thermal fatigue test. This correlates the thermal damage generated in the cylinder head during the thermal fatigue test with the thermal damage of the cylinder head on the engine, thus more accurately evaluating the low-cycle fatigue performance of the cylinder head.

Description

Technical Field

[0001] This application belongs to the field of cylinder head thermal fatigue testing technology, and particularly relates to a method, system, equipment and medium for determining the loading temperature of cylinder head thermal fatigue testing. Background Technology

[0002] Cylinder head thermal fatigue testing is a common method for evaluating the low-cycle fatigue life of cylinder heads. By cyclically loading the cylinder head from its lowest to its highest loading temperature, stress changes are induced in the cylinder head's burner plates, thus achieving the goal of assessing low-cycle fatigue life. In cylinder head thermal fatigue testing, the lowest cyclic loading temperature is typically set at the cylinder head's idle temperature or the temperature at which the thermal stress in the burner plates is approximately zero. The highest loading temperature then becomes a crucial factor affecting the stress amplitude and degree of thermal damage to the burner plates during the test. Therefore, determining the highest loading temperature to accurately reflect the low-cycle fatigue performance of the cylinder head is key to effective thermal fatigue testing.

[0003] Currently, the temperature of the fire plate under rated engine conditions or the highest temperature of the fire plate during engine operation is often used as the maximum loading temperature for thermal fatigue testing. This ignores the difference in internal temperature gradient of the fire plate caused by the different cooling methods and cooling rates of the cylinder head between the thermal fatigue testing device and the engine. Therefore, the thermal damage generated at the fire plate in the test is significantly different from the thermal damage generated at the fire plate in the engine, and the test results obtained cannot truly reflect the low-cycle fatigue performance of the cylinder head. Summary of the Invention

[0004] In view of this, this application aims to provide a method, system, equipment and medium for determining the loading temperature of cylinder head thermal fatigue test, in order to solve at least one of the above problems.

[0005] To achieve the above objectives, the technical solution of this application is implemented as follows: In a first aspect, this application provides a method for determining the loading temperature of a cylinder head thermal fatigue test, including: A whole-machine temperature measurement test was performed on the cylinder head installed on the engine, and the first temperature measurement data on the engine cylinder head was obtained. The engine cylinder head temperature field simulation model was calibrated based on the first temperature measurement data. Based on the calibrated temperature boundary with one loading cycle and the physical conditions of the engine cylinder head, the stress data and plastic strain data of the engine cylinder head model within the preset cycle of cyclic loading are obtained through finite element analysis software. The stress data and plastic strain data are input into fatigue analysis software to output the minimum low-cycle fatigue life of the engine cylinder head, and the position corresponding to the minimum low-cycle fatigue life is taken as the low-cycle fatigue danger point of the engine cylinder head. By performing a temperature measurement test on the cylinder head installed on the thermal fatigue testing device, and cyclically loading the cylinder head on the thermal fatigue testing device, the second temperature measurement data of the key areas of the fire plate within one loading cycle is obtained. The thermal fatigue test cylinder head temperature field simulation model is calibrated using the second temperature measurement data. Combined with the calibrated temperature boundary with one loading cycle and the physical conditions of the thermal fatigue test cylinder head, the stress data and plastic strain data of the thermal fatigue test cylinder head model within the preset cycle of cyclic loading are obtained through finite element analysis software. The stress data and plastic strain data are then input into the fatigue analysis software to output the low-cycle fatigue life of the cylinder head of the thermal fatigue test device corresponding to the low-cycle fatigue danger point of the engine cylinder head. The minimum low-cycle fatigue life of the cylinder head under engine operating conditions is compared with the low-cycle fatigue life of the cylinder head at the corresponding low-cycle fatigue danger point in the engine cylinder head during thermal fatigue testing. The loading temperature of the low-cycle fatigue danger point in the cylinder head thermal fatigue test is determined based on the deviation comparison results.

[0006] Secondly, based on the same inventive concept, this application also provides a cylinder head thermal fatigue test loading temperature determination system, comprising: The first temperature measurement test module is configured to perform a whole-machine temperature measurement test on the cylinder head installed on the engine, and obtain the first temperature measurement data on the engine cylinder head, and calibrate the engine cylinder head temperature field simulation model based on the first temperature measurement data. The first simulation analysis module is configured to obtain stress data and plastic strain data of the engine cylinder head model within a preset cycle of cyclic loading using finite element analysis software, based on the calibrated temperature boundary with one loading cycle and the physical conditions of the engine cylinder head. The stress data and plastic strain data are then input into fatigue analysis software to output the minimum low-cycle fatigue life of the engine cylinder head, and the location corresponding to the minimum low-cycle fatigue life is taken as the low-cycle fatigue danger point of the engine cylinder head. The second temperature measurement test module is configured to perform a temperature measurement test on the cylinder head installed on the thermal fatigue test device, and to cyclically load the cylinder head on the thermal fatigue test device to obtain the second temperature measurement data of the key area measurement points on the fire plate within one loading cycle. The second simulation analysis module is configured to calibrate the temperature field simulation model of the cylinder head for thermal fatigue testing using the second temperature measurement data. Combining the calibrated temperature boundary with one loading cycle and the physical conditions of the cylinder head for thermal fatigue testing, the module obtains the stress data and plastic strain data of the cylinder head model for thermal fatigue testing within a preset cyclic loading cycle using finite element analysis software. The stress data and plastic strain data are then input into the fatigue analysis software to output the low-cycle fatigue life of the cylinder head of the engine corresponding to the low-cycle fatigue danger point of the cylinder head of the thermal fatigue testing device. The loading temperature determination module is configured to compare the minimum low-cycle fatigue life of the cylinder head under engine operating conditions with the low-cycle fatigue life of the cylinder head at the corresponding low-cycle fatigue danger point position in the engine cylinder head during thermal fatigue testing, and determine the loading temperature of the low-cycle fatigue danger point in the cylinder head thermal fatigue test based on the deviation comparison result.

[0007] Thirdly, based on the same inventive concept, this application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the method described in the first aspect.

[0008] Fourthly, based on the same inventive concept, this application also provides a non-transitory computer-readable storage medium, wherein the non-transitory computer-readable storage medium stores computer instructions for causing the computer to perform the method as described in the first aspect.

[0009] Compared with the prior art, the method, system, equipment and medium for determining the loading temperature of cylinder head thermal fatigue test described in this application have the following advantages: (1) The method described in this application can compensate for the difference in thermal damage in the fire plate area caused by the different cooling methods and cooling rates of the cylinder head in the thermal fatigue test device and engine bench by optimizing the loading temperature of the cylinder head thermal fatigue test, so that the thermal damage generated in the cylinder head in the thermal fatigue test is related to the thermal damage of the cylinder head on the engine, and the low-cycle fatigue performance of the cylinder head can be evaluated more accurately.

[0010] (2) The method described in this application can adapt to cylinder head thermal fatigue tests with different cooling methods such as air cooling and water cooling. It has wide applicability and provides theoretical support for determining the load boundary of cylinder head thermal fatigue tests. Attached Figure Description

[0011] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a flowchart of a method for determining the loading temperature of a cylinder head thermal fatigue test according to an embodiment of this application; Figure 2 This is a schematic diagram of the arrangement of measuring points on the fire plate of the engine cylinder head (cylinder head I) for the whole engine temperature measurement test, as described in the embodiments of this application. Figure 3 This is a schematic diagram of the temperature measuring point arrangement of the cylinder head (cylinder head II) fire plate of the thermal fatigue testing device described in this application embodiment; Figure 4This is a schematic diagram of a cylinder head thermal fatigue test loading temperature determination system according to an embodiment of this application; Figure 5 This is a schematic diagram of the hardware structure of the electronic device described in an embodiment of this application. Detailed Implementation

[0012] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0013] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0014] The embodiments of this application are described in detail below with reference to the accompanying drawings.

[0015] Please see Figure 1 As shown in the figure, this embodiment provides a method for determining the loading temperature of a cylinder head thermal fatigue test, which specifically includes the following steps: Step S101: Perform a whole-machine temperature measurement test on the cylinder head installed on the engine and obtain the first temperature measurement data on the engine cylinder head. Based on the first temperature measurement data, calibrate the engine cylinder head temperature field simulation model.

[0016] Specifically, in this embodiment, cylinder head I is used as the cylinder head for the engine whole-machine temperature measurement test. n (n≥7) measuring points are set on the fire plate of cylinder head I, and temperature sensors are arranged at these measuring points, such as... Figure 2 As shown, the exhaust nose bridge area is a region where low-cycle fatigue risks are likely to occur, and the number of measuring points should not be less than 3. The number of measuring points in the intake nose bridge area should not be less than 2. The number of measuring points in the nose bridge area between the intake and exhaust should not be less than 2.

[0017] The cylinder head I was installed on the engine for whole-machine temperature measurement test. The engine was set to a loading cycle from idle condition to rated condition. When the temperature change stabilized within one loading cycle, the temperature change of n measuring points on the fire plate was recorded by temperature sensor within one loading cycle. The engine cylinder head temperature field simulation model was calibrated based on the obtained temperature measurement data. The temperature simulation value of each measuring point within one loading cycle deviated from the whole-machine temperature measurement test result by ≤10%.

[0018] Step S102: Based on the calibrated temperature boundary with one loading cycle and the physical conditions of the engine cylinder head, obtain the stress data and plastic strain data of the engine cylinder head model within the preset cycle of cyclic loading using finite element analysis software. Input the stress data and plastic strain data into the fatigue analysis software to output the minimum low-cycle fatigue life of the engine cylinder head, and take the position corresponding to the minimum low-cycle fatigue life as the low-cycle fatigue danger point of the engine cylinder head.

[0019] Specifically, in this embodiment, based on the calibrated temperature boundary of a loading cycle, as well as the preload of the engine cylinder head bolts and the plasticity characteristics of the cylinder head material, the stress and plastic strain of the engine cylinder head model under i cycles of cyclic loading are calculated in the Abaqus finite element analysis software. To ensure that the periodic change of the plastic strain of the fire plate tends to be stable so that i ≥ 5, the low-cycle fatigue life of the cylinder head under the engine working environment is calculated. The *.odb result file generated by the analysis software is imported into the FEMFAT fatigue analysis software. Using the "HEAT Sehitoglu" module, the stress and plastic strain of the cylinder head in the i-th cycle are used as the calculation input to calculate the minimum low-cycle fatigue life of the cylinder head, denoted as X. The location of X is the low-cycle fatigue danger point of the cylinder head.

[0020] Step S103: Perform a temperature measurement test on the cylinder head installed on the thermal fatigue test device, and cyclically load the cylinder head on the thermal fatigue test device to obtain the second temperature measurement data of the key monitoring area on the fire plate within one loading cycle.

[0021] Specifically, in this embodiment, a thermal fatigue testing device is used to measure the temperature of the cylinder head. The bridge area, where the low-cycle fatigue risk point calculated in step S102 is located, is designated as the key area of ​​concern. Cylinder head II is used as the cylinder head for thermal fatigue testing. Figure 3 As shown, three measuring points A, B, and C are set up in the nose bridge area and temperature sensors are arranged there. Among them, measuring point A is located at the fatigue danger point calculated in step S102. The cylinder head II is installed on the thermal fatigue test device with a bolt preload equivalent to the preload of the cylinder head bolts on the engine.

[0022] Cyclic loading is applied to cylinder head II on the thermal fatigue testing device. When the temperature change stabilizes within one loading cycle, the minimum and maximum loading temperatures of measuring points A, B, and C should deviate from the loading temperatures of the corresponding positions on the engine cylinder head under idle and rated conditions by ≤10%, respectively. The temperature changes of measuring points A, B, and C on the fire plate within one loading cycle are recorded by temperature sensors.

[0023] Step S104: The temperature field simulation model of the cylinder head for thermal fatigue testing is calibrated using the second temperature measurement data. Combined with the calibrated temperature boundary with one loading cycle and the physical conditions of the cylinder head for thermal fatigue testing, the stress data and plastic strain data of the cylinder head model for thermal fatigue testing within the preset cyclic loading cycle are obtained using finite element analysis software. The stress data and plastic strain data are then input into the fatigue analysis software to output the low-cycle fatigue life of the cylinder head of the engine corresponding to the low-cycle fatigue danger point of the cylinder head of the thermal fatigue testing device.

[0024] Specifically, in this embodiment, the cylinder head temperature field simulation model for the cylinder head thermal fatigue test is calibrated based on the temperature measurement data of measuring points A, B, and C in step S103. The temperature simulation values ​​of points A, B, and C on the simulation model within one loading cycle are ≤10% different from the temperature values ​​of the corresponding three points measured by the thermal fatigue test device.

[0025] Based on the calibrated temperature boundary of one loading cycle, and conditions such as the preload of the cylinder head bolts and the plasticity of the cylinder head material in the thermal fatigue testing device, the stress and plastic strain of the cylinder head of the thermal fatigue testing device model in j loading cycles are calculated in the Abaqus finite element analysis software. To ensure that the periodic change of the plastic strain of the fire plate tends to be stable, j≥5, the low-cycle fatigue life of the cylinder head on the thermal fatigue testing device is calculated. The *.odb result file generated by the software is imported into the FEMFAT fatigue analysis software. Using the "HEAT Sehiitoglu" module, the stress and plastic strain of the j-th cycle are used as the calculation input, and the low-cycle fatigue life of point A is calculated and denoted as Y1.

[0026] Step S105: Compare the minimum low-cycle fatigue life of the cylinder head under engine operating conditions with the low-cycle fatigue life of the cylinder head at the corresponding low-cycle fatigue danger point in the thermal fatigue test, and determine the loading temperature of the low-cycle fatigue danger point in the cylinder head thermal fatigue test based on the deviation comparison result.

[0027] Specifically, in this embodiment, the minimum low-cycle fatigue life X of the cylinder head under the engine working environment in step S102 and the low-cycle fatigue life Y1 of the cylinder head in the thermal fatigue test in step S104 are compared. If the deviation between Y1 and X is ≥10%, the thermal damage is inconsistent. The temperature of point A under engine idling and rated conditions cannot be directly used as the minimum and maximum loading temperatures for assessment on the thermal fatigue testing device. The loading temperature of the low-cycle fatigue danger point (point A) in the thermal fatigue testing device needs to be optimized so as to compensate for the difference in thermal damage caused by the different cooling methods and cooling rates of the cylinder head between the thermal fatigue testing device and the engine.

[0028] If Y1 is greater than X, then the calculation of low-cycle fatigue life at point A of the cylinder head fire plate in the thermal fatigue test is increased by the maximum loading temperature; conversely, the calculation of low-cycle fatigue life at point A of the cylinder head fire plate in the thermal fatigue test is decreased by the maximum loading temperature, until the low-cycle fatigue life value Y1 at point A of the cylinder head fire plate on the thermal fatigue testing device is reached. k If the difference between (k=1, 2, 3…) and X is ≤10%, it is considered that the thermal damage at point A under the engine working environment and the thermal fatigue test conditions is consistent. The loading temperature at point A at this time is recorded as the loading temperature of the low-cycle fatigue danger point (point A) in the cylinder head thermal fatigue test.

[0029] The cylinder head thermal fatigue test loading temperature determination method described in this embodiment can compensate for the differences in thermal damage in the fire plate area caused by the different cooling methods and cooling rates of the cylinder head in the thermal fatigue test device and engine bench by optimizing the cylinder head thermal fatigue test loading temperature. This makes the thermal damage generated in the cylinder head during the thermal fatigue test assessment correlated with the thermal damage of the cylinder head on the engine, and more accurately evaluates the low-cycle fatigue performance of the cylinder head.

[0030] It should be noted that the above description describes some embodiments of this application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in a different order than that shown in the above embodiments and still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0031] Based on the same inventive concept, and corresponding to any of the above embodiments, the embodiments of this application also provide a cylinder head thermal fatigue test loading temperature determination system.

[0032] like Figure 4 As shown, the cylinder head thermal fatigue test loading temperature determination system includes: The first temperature measurement test module 11 is configured to perform a whole-machine temperature measurement test on the cylinder head installed on the engine, and obtain the first temperature measurement data on the engine cylinder head, and calibrate the engine cylinder head temperature field simulation model based on the first temperature measurement data. The first simulation analysis module 12 is configured to obtain stress data and plastic strain data of the engine cylinder head model within a preset cycle of cyclic loading through finite element analysis software based on the calibrated temperature boundary with one loading cycle and the physical conditions of the engine cylinder head. The stress data and plastic strain data are then input into fatigue analysis software to output the minimum low-cycle fatigue life of the engine cylinder head, and the position corresponding to the minimum low-cycle fatigue life is taken as the low-cycle fatigue danger point of the engine cylinder head. The second temperature measurement test module 13 is configured to perform a temperature measurement test on the cylinder head installed on the thermal fatigue test device and cyclically load the cylinder head on the thermal fatigue test device to obtain the second temperature measurement data of the key area measurement point on the fire plate within a loading cycle. The second simulation analysis module 14 is configured to calibrate the temperature field simulation model of the cylinder head for thermal fatigue testing using the second temperature measurement data. Combining the calibrated temperature boundary with one loading cycle and the physical conditions of the cylinder head for thermal fatigue testing, the module obtains the stress data and plastic strain data of the cylinder head model for thermal fatigue testing within a preset cyclic loading cycle using finite element analysis software. The stress data and plastic strain data are then input into the fatigue analysis software to output the low-cycle fatigue life of the cylinder head of the engine corresponding to the low-cycle fatigue danger point of the cylinder head of the thermal fatigue testing device. The loading temperature determination module 15 is configured to compare the minimum low-cycle fatigue life of the cylinder head under engine operating conditions with the low-cycle fatigue life of the cylinder head at the corresponding low-cycle fatigue danger point position in the thermal fatigue test, and determine the loading temperature of the low-cycle fatigue danger point in the cylinder head thermal fatigue test based on the deviation comparison result.

[0033] For ease of description, the above system is described by dividing it into various modules based on their functions. Of course, in implementing the embodiments of this application, the functions of each module can be implemented in one or more software and / or hardware.

[0034] The system described in the above embodiments is used to implement the corresponding method in any of the foregoing embodiments and has the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0035] Based on the same inventive concept, corresponding to the methods of any of the above embodiments, embodiments of this application also provide an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the methods described in any of the above embodiments.

[0036] Figure 5 This embodiment illustrates a more specific hardware structure of an electronic device, which may include a processor 1010, a memory 1020, an input / output interface 1030, a communication interface 1040, and a bus 1050. The processor 1010, memory 1020, input / output interface 1030, and communication interface 1040 are interconnected internally via the bus 1050.

[0037] The processor 1010 can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this specification.

[0038] The memory 1020 can be implemented in the form of ROM (Read Only Memory), RAM (Random Access Memory), static storage device, dynamic storage device, etc. The memory 1020 can store the operating system and other applications. When the technical solutions provided in the embodiments of this specification are implemented by software or firmware, the relevant program code is stored in the memory 1020 and is called and executed by the processor 1010.

[0039] The input / output interface 1030 is used to connect input / output modules to realize information input and output. The input / output modules can be configured as components in the device (not shown in the figure) or externally connected to the device to provide corresponding functions. Input devices may include keyboards, mice, touch screens, microphones, various sensors, etc., and output devices may include displays, speakers, vibrators, indicator lights, etc.

[0040] The communication interface 1040 is used to connect a communication module (not shown in the figure) to enable communication between this device and other devices. The communication module can communicate via wired means (such as USB, Ethernet cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.).

[0041] Bus 1050 includes a pathway for transmitting information between various components of the device, such as processor 1010, memory 1020, input / output interface 1030, and communication interface 1040.

[0042] It should be noted that although the above-described device only shows the processor 1010, memory 1020, input / output interface 1030, communication interface 1040, and bus 1050, in specific implementations, the device may also include other components necessary for normal operation. Furthermore, those skilled in the art will understand that the above-described device may only include the components necessary for implementing the embodiments of this specification, and not necessarily all the components shown in the figures.

[0043] The electronic devices described above are used to implement the corresponding methods in any of the foregoing embodiments and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0044] Based on the same inventive concept, corresponding to the methods of any of the above embodiments, this application also provides a non-transitory computer-readable storage medium that stores computer instructions for causing the computer to perform the methods described in any of the above embodiments.

[0045] The computer-readable medium of this embodiment includes permanent and non-permanent, removable and non-removable media, and information storage can be implemented by any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transfer medium that can be used to store information accessible by a computing device.

[0046] The computer instructions stored in the storage medium of the above embodiments are used to cause the computer to perform the method described in any of the above embodiments, and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0047] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of this application (including the claims) is limited to these examples; within the framework of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the embodiments of this application as described above, which are not provided in the details for the sake of brevity.

[0048] Although this application has been described in conjunction with specific embodiments thereof, many substitutions, modifications, and variations of these embodiments will be apparent to those skilled in the art from the foregoing description. For example, other memory architectures (e.g., dynamic RAM (DRAM)) may be used with the embodiments discussed.

[0049] The embodiments of this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this application should be included within the protection scope of this application.

Claims

1. A method for determining the loading temperature in a cylinder head thermal fatigue test, characterized in that, include: A whole-machine temperature measurement test was performed on the cylinder head installed on the engine, and the first temperature measurement data on the engine cylinder head was obtained. The engine cylinder head temperature field simulation model was calibrated based on the first temperature measurement data. Based on the calibrated temperature boundary with one loading cycle and the physical conditions of the engine cylinder head, the stress data and plastic strain data of the engine cylinder head model within the preset cycle of cyclic loading are obtained through finite element analysis software. The stress data and plastic strain data are input into fatigue analysis software to output the minimum low-cycle fatigue life of the engine cylinder head, and the position corresponding to the minimum low-cycle fatigue life is taken as the low-cycle fatigue danger point of the engine cylinder head. By performing a temperature measurement test on the cylinder head installed on the thermal fatigue testing device, and cyclically loading the cylinder head on the thermal fatigue testing device, the second temperature measurement data of the key areas of the fire plate within one loading cycle is obtained. The thermal fatigue test cylinder head temperature field simulation model is calibrated using the second temperature measurement data. Combined with the calibrated temperature boundary with one loading cycle and the physical conditions of the thermal fatigue test cylinder head, the stress data and plastic strain data of the thermal fatigue test cylinder head model within the preset cycle of cyclic loading are obtained through finite element analysis software. The stress data and plastic strain data are then input into the fatigue analysis software to output the low-cycle fatigue life of the cylinder head of the thermal fatigue test device corresponding to the low-cycle fatigue danger point of the engine cylinder head. The minimum low-cycle fatigue life of the cylinder head under engine operating conditions is compared with the low-cycle fatigue life of the cylinder head at the corresponding low-cycle fatigue danger point in the engine cylinder head during thermal fatigue testing. The loading temperature of the low-cycle fatigue danger point in the cylinder head thermal fatigue test is determined based on the deviation comparison results.

2. The method of claim 1, wherein, Before the overall temperature measurement test, the following is included: Several measuring points are set on the fire plate of the engine cylinder head, and temperature sensors are arranged at the corresponding measuring points; among them, the number of measuring points located in the exhaust nose area is not less than three, the number of measuring points located in the intake nose area is not less than two, and the number of measuring points located in the intake and exhaust nose area is not less than two.

3. The method according to claim 1, characterized in that: The engine is set to operate from idle to rated operating condition as one loading cycle. Once the temperature changes stabilize within one loading cycle, the temperature changes at various measuring points on the fire control plate are recorded by temperature sensors within one loading cycle.

4. The method according to claim 1, characterized in that: The temperature simulation values ​​at each measuring point within one loading cycle deviate from the overall machine temperature measurement test results by ≤10%.

5. The method according to claim 1, characterized in that: When conducting temperature measurement tests using a thermal fatigue testing device, the nose bridge area, where the low-cycle fatigue hazard point of the engine cylinder head is located, is taken as the key area of ​​focus. Multiple measuring points are set up in the nose bridge area and temperature sensors are arranged there, with one of the measuring points being the low-cycle fatigue hazard point of the engine cylinder head. By cyclically loading the cylinder head on the thermal fatigue testing device, when the temperature change is stable within one loading cycle, the minimum and maximum loading temperatures of multiple measuring points are respectively ≤10% different from the loading temperatures of the corresponding positions on the engine cylinder head under idle and rated conditions. The temperature changes of multiple measuring points on the fire plate are recorded by temperature sensors within one loading cycle.

6. The method according to claim 5, characterized in that: The cylinder head temperature field simulation model for thermal fatigue testing is calibrated based on the second temperature measurement data obtained at the measuring points. The temperature simulation values ​​of multiple measuring points on the simulation model within one loading cycle are ≤10% different from the temperature values ​​of the corresponding points in the thermal fatigue testing device.

7. The method according to claim 1, characterized in that: If the deviation comparison result meets the preset threshold, it is determined that the thermal damage of a measuring point at the corresponding low-cycle fatigue danger point of the engine cylinder head is consistent with that under the engine working environment and the thermal fatigue test conditions. The loading temperature of the measuring point at the corresponding low-cycle fatigue danger point of the engine cylinder head at this time is recorded as the loading temperature of the low-cycle fatigue danger point in the cylinder head thermal fatigue test. If the deviation comparison result does not meet the preset threshold, the loading temperature of the low-cycle fatigue danger point in the cylinder head thermal fatigue test device is optimized.

8. A cylinder head thermal fatigue test loading temperature determination system characterized by, include: The first temperature measurement test module is configured to perform a whole-machine temperature measurement test on the cylinder head installed on the engine, and acquire the first temperature measurement data on the engine cylinder head, and calibrate the engine cylinder head temperature field simulation model based on the first temperature measurement data. The first simulation analysis module is configured to obtain stress data and plastic strain data of the engine cylinder head model within a preset cycle of cyclic loading using finite element analysis software, based on the calibrated temperature boundary with one loading cycle and the physical conditions of the engine cylinder head. The stress data and plastic strain data are then input into fatigue analysis software to output the minimum low-cycle fatigue life of the engine cylinder head, and the location corresponding to the minimum low-cycle fatigue life is taken as the low-cycle fatigue danger point of the engine cylinder head. The second temperature measurement test module is configured to perform a temperature measurement test on the cylinder head installed on the thermal fatigue test device, and to cyclically load the cylinder head on the thermal fatigue test device to obtain the second temperature measurement data of the key area measurement points on the fire plate within one loading cycle. The second simulation analysis module is configured to calibrate the temperature field simulation model of the cylinder head for thermal fatigue testing using the second temperature measurement data. Combining the calibrated temperature boundary with one loading cycle and the physical conditions of the cylinder head for thermal fatigue testing, the module obtains the stress and plastic strain data of the cylinder head model for thermal fatigue testing within a preset cyclic loading cycle using finite element analysis software. The stress and plastic strain data are then input into the fatigue analysis software to output the low-cycle fatigue life of the cylinder head of the engine corresponding to the low-cycle fatigue danger point of the cylinder head of the thermal fatigue testing device. The loading temperature determination module is configured to compare the minimum low-cycle fatigue life of the cylinder head under engine operating conditions with the low-cycle fatigue life of the cylinder head at the corresponding low-cycle fatigue danger point position in the engine cylinder head during thermal fatigue testing, and determine the loading temperature of the low-cycle fatigue danger point in the cylinder head thermal fatigue test based on the deviation comparison result.

9. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the method as described in any one of claims 1-7.

10. A non-transitory computer-readable storage medium, comprising: in, The non-transitory computer-readable storage medium stores computer instructions for causing a computer to perform the method described in any one of claims 1-7.

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