Method, medium, terminal, and application for compiling load spectrum of high-temperature components of aeroengine

Abstract

The present invention discloses a method, medium, terminal, and application for compiling a load spectrum of high-temperature components of an aeroengine, relating to the technical field of aeroengine structural integrity. By combining the operating conditions and measured flight data, a thermo-mechanical multi-field coupling analysis is performed on the evaluated high-temperature components to determine the life assessment region and its typical state parameters under load; an equivalent conversion model between fatigue-creep load and fatigue load is established; to determine the model parameters, the calculated state parameters are used as input conditions to conduct material tests to determine the number of life cycles and damage indices corresponding to each stress level and hold time; in the data compression process, the duration of the equivalent and small-amplitude cycles is identified and converted into fatigue cycles using the established equivalent conversion model. The present invention introduces an equivalent conversion model of fatigue-creep load built based on material tests and simulation analysis as a technical hub between the failure mechanisms of structures and materials and the cycle counting process.

Description

Technical Field

[0001] The present invention discloses a technology related to the structural integrity of aero-engines, in particular to a method for compiling a load spectrum suitable for high-temperature components of aero-engines, a computer-readable storage medium, and an information data processing terminal. Background Art

[0002] The research on the structural integrity of aero-engines depends to a great extent on the authenticity of the load spectrum. The load spectrum is obtained by appropriately compressing the load-time history of the measured flight data. The current statistical processing of this random load history mainly adopts the rainflow counting method. The rainflow counting method is a two-parameter counting method proposed based on the relationship between material fatigue damage and stress / strain. Since its counting rule is consistent with the stress-strain hysteresis loop, it can simply extract the key information independent of time (the mean amplitude cycle). There is a good correlation between the life estimation results obtained based on this method and the test results.

[0003] The classical rainflow counting method is divided into two steps: data compression (steps such as pseudo-data replacement, equal-value point compression, peak-valley value detection, and small amplitude removal) and cycle extraction. Equal-value point compression and invalid amplitude omission are simplified steps based on the idea that damage is completely contributed by fatigue cycles. A large number of small cycles outside the main cycle in the load history (especially those with an amplitude below 10%) are filtered out, and only the fatigue cycle information is retained. Its theoretical basis is that at lower temperature conditions, the time-dependent creep behavior of materials can usually be ignored. However, for hot-end components (such as aero-engine turbine disks) with extreme and complex loading conditions, the creep behavior of materials becomes significant at high temperatures, and the fatigue-creep interaction during the hold time significantly limits their service life. Obviously, if the traditional rainflow counting method is used at this time, a considerable part of the damage contributed by small cycle loads with a longer time or a larger mean stress will be ignored, and the life prediction will be on the dangerous side.

[0004] The difficulty in solving the above technical problem lies in that in the existing methods in this field, only small cycles below a certain threshold are regarded as not contributing to damage and are all eliminated. Practice has shown that the creep behavior of materials at high temperatures has brought unacceptable and dangerous life assessment results due to the simple elimination of small amplitudes. This problem has always lacked a solution with certain theoretical and experimental support and is easy to implement, becoming one of the chronic diseases in the field of structural integrity.

[0005] The significance of solving the above technical problems lies in that the existing spectrum compilation methods for processing small cycles in the load history are based on experience to set a certain threshold (by stress, percentage or fatigue strength limit and other standards) and then consider that its contribution damage can be ignored and therefore be eliminated. These methods lack theoretical and experimental support for their rationality and accuracy. It is particularly important to note that the load spectrum processing work actually has large individual differences. Even if a more reasonable threshold is explored in the application, it is generally no longer applicable to engines of different models, use units and environments, and flight missions, and needs to be re-determined. For high temperature conditions, the existing methods cannot quantitatively consider the creep contribution of small cycle loads and the increasing trend of fatigue-creep coupling damage as the temperature rises, so the life prediction results given by them are only of reference value. The present invention is based on the fatigue-creep equivalent conversion model determined by material testing, and can quantitatively convert a large number of small cycles in the load-time series (small cycles less than 3% of the maximum value in a certain speed spectrum can account for more than 95% of the total number of cycles) and other damage and include them in the cycle extraction matrix. In particular, the load spectrum compilation strategy for high temperature conditions has been optimized, which better balances load compression and fidelity, providing technical support for damage assessment, life prediction and other security work. Summary of the invention

[0006] In view of the problem that existing high-temperature load processing methods ignore or insufficiently consider damage during the holding time, the present invention discloses a load spectrum compilation method suitable for high-temperature components of aircraft engines. Based on the generalized fatigue-creep load equivalent conversion theory, an equivalent conversion modeling method covering all working conditions (arbitrary load level, temperature, and holding time) is provided by relying on material tests. The holding time composed of a large number of small-amplitude cycles and equivalent points in the load-time history is considered, and the processes such as compression of equivalent points and invalid amplitude in load processing are optimized to improve the life prediction accuracy of high-temperature components of aircraft engines with extreme and complex service environments. Once the model is established, the equivalent conversion ratio of small cycles (including equivalent loads) can be adaptively adjusted to cope with differentiated load spectra. The present disclosure has engineering value for the compilation of load spectra in other fields (agricultural machinery, aviation, rail transit) and alloy materials.

[0007] The load spectrum compilation method applicable to high-temperature components of an aero-engine comprises the following steps:

[0008] Step 1: Combine the operating conditions and measured flight data to conduct a thermal-mechanical multi-field coupling analysis on the high-temperature components to determine the life assessment area and its typical state parameters;

[0009] Step 2: Establish an equivalent conversion model between fatigue-creep load and fatigue load;

[0010] Step 3: To determine the model parameters, use the calculated state parameters as input conditions, conduct material tests, and determine the number of life cycles and damage indices corresponding to each stress level and holding time.

[0011] Step 4: Identify the duration of equivalent and small-amplitude cycles in the data compression process, convert them into fatigue cycles using the established equivalent conversion model, and superimpose the fatigue cycle statistical matrix obtained from the cycle counting process to obtain the total cycle statistical matrix, and verify the life prediction accuracy.

[0012] In one embodiment, the conducting of the material tests includes: tensile tests, fatigue tests, and fatigue-creep tests under single and combined loadings.

[0013] In one embodiment, Step 1 specifically includes the following steps:

[0014] First step: Determine the common and typical operating condition intervals.

[0015] Second step: Determine the boundary conditions for finite element calculation according to the actual loading conditions of the component under assessment, and conduct multi-field coupling solution.

[0016] In one embodiment, the establishment of the equivalent conversion model between the fatigue-creep load and the fatigue load includes the following steps:

[0017] First step: Determine that the model architecture for load conversion processing is in the form of a second-order polynomial:

[0018]

[0019] c i is the material parameter;

[0020] Second step: Determine the relationship between the material tensile strength and temperature from the material tensile test.

[0021] Third step: According to the finite element calculation results, determine the equivalent stress corresponding to the stress S T at each temperature T corresponding to the reference temperature T0

[0022] Fourth step: Conduct low-cycle fatigue tests, and determine the damage index and then the model parameters from the number of life cycles corresponding to different holding times under single and multi-level stress levels of combined loading.

[0023] In one embodiment, determining that the model architecture for load conversion processing is in the form of a second-order polynomial specifically includes the following steps:

[0024] First step: Based on the generalized equivalent conversion theory of fatigue-creep loads, determine the load processing method for high-temperature conditions.

[0025] According to the fatigue-creep load equivalent conversion theory, if a set of fatigue-creep composite (holding time t B ≠0) loading and another group of pure fatigue with the same peak-to-valley value (t B =0) the damage contributed by the loading is equal, that is:

[0026]

[0027] Step 2: Determine the model architecture for load conversion processing;

[0028] According to formula (2), the equivalent conversion ratio of fatigue load to fatigue-creep combined load can be obtained: Definition:

[0029]

[0030] Where a and b are the damage indices of pure fatigue and fatigue-creep combined loading, respectively; N f , are the corresponding lifespans of the two, and the above parameters are obtained from low-cycle fatigue tests; corresponding to a certain working condition (stress level S, load holding time t B , temperature T), The meaning is: B ≠0, the damage contributed by one cycle is equivalent to t B =0 o'clock cycles;

[0031] The third step is to simplify and adjust the model architecture adaptively based on actual application conditions.

[0032] According to the general stress standard, the fatigue damage caused by the stress level at temperature T to the material depends on the stress S T The tensile strength of the material at temperature T Therefore, the stress S corresponding to the temperature T of each operating point in the solution result is T All are converted into equivalent stress at a certain reference temperature T0

[0033]

[0034] Thus, the equivalent conversion ratio The definition can be simplified to a form containing only two parameters:

[0035]

[0036] The left side of the above formula can be determined by polynomial series approximation, and the coefficients are obtained from the least squares regression test data; considering the fitting accuracy and solution difficulty, the second-order polynomial form is selected:

[0037]

[0038] c i is the material parameter.

[0039] In one embodiment, step three specifically includes the following:

[0040] First step, conduct the material tensile test at different temperatures; obtain the relationship between the tensile strength and temperature of the material at different temperatures by fitting the tensile tests at different temperatures;

[0041] Second step, conduct the low-cycle fatigue test under single and combined loadings; use the reference temperature T0 and its corresponding equivalent stress in the finite element calculation results as the input conditions;

[0042] Third step, determine the model parameters using the test data; determine the damage index of each level of load by the nonlinear damage accumulation method using the life cycle data of the single and combined loading tests, and substitute it into the definition formula of the equivalent conversion ratio of fatigue load and fatigue-creep composite load to determine the model parameters and complete the modeling.

[0043] In one embodiment, step four specifically includes the following:

[0044] First step, equivalent point processing; before extracting the peak and valley values in the rainflow counting process, identify the duration of the equivalent load, call the model to convert it into a fatigue cycle and compress it into one point in the original load-time history;

[0045] Second step, small-amplitude cycle processing; after extracting the peak and valley values, identify the peak and valley values of the small-amplitude cycles in the interval above the slow speed, identify the positions of the cycle peak and valley values in the original history to calculate the hold time between them, and convert them into fatigue cycles by the model; the small amplitude is defined as less than a certain speed or stress percentage threshold, and the threshold is determined by the change trend of the total damage value when removing different amplitudes;

[0046] Third step, complete the statistics; obtain the total cycle statistical matrix, and superimpose the asymmetric stress cycle statistical matrix obtained in the cycle extraction step on the converted fatigue cycle statistical matrix obtained in the previous steps to obtain the total cycle statistical matrix;

[0047] Fourth step, verify the accuracy of life prediction; obtain the damage values of the T-RC and I-RC methods using the life-time fraction prediction method.

[0048] Another object of the present invention is to provide a computer-readable storage medium storing a computer program, which when executed by a processor, causes the processor to execute the load spectrum compilation method applicable to high-temperature components of an aeroengine.

[0049] Another object of the present invention is to provide an information data processing terminal, which includes a memory and a processor. The memory stores a computer program. When the computer program is executed by the processor, the processor executes the load spectrum compilation method applicable to high-temperature components of an aero-engine.

[0050] Another object of the present invention is to provide an aero-engine that implements the load spectrum compilation method applicable to high-temperature components of an aero-engine.

[0051] The technical solutions provided by the disclosed embodiments of the present invention have the following beneficial effects:

[0052] The present invention introduces a fatigue-creep load equivalent conversion model built based on material tests and simulation analysis as the technical hub between the failure mechanisms of structures and materials and the cycle counting process. Quantitatively convert and account for a large number of small cycles in the load-time series and the damage during the hold time into the cycle extraction matrix in an equivalent damage manner. Once the model is established, this process can adaptively adjust for different load histories. Taking the life prediction of a certain type of engine turbine disk as a verification, the prediction accuracy of the present invention is improved by two orders of magnitude compared with the existing methods, and the optimization effect is obvious. The present invention provides a breakthrough solution for the compilation of load spectra for components made of metallic materials under various working environments and working histories, and has considerable engineering application prospects. Description of the Drawings

[0053] The drawings herein are incorporated into the specification and form a part of this specification, showing embodiments consistent with the present disclosure, and are used together with the specification to explain the principles of the present disclosure.

[0054] Figure 1 is the implementation flowchart of the load spectrum compilation method applicable to high-temperature components of an aero-engine provided by the present invention.

[0055] Figure 2 is the theoretical schematic diagram of step S2 provided by the present invention.

[0056] Figure 3 is the schematic diagram of the modeling result of step S3 provided by the present invention.

[0057] Figure 4 is the implementation flowchart of step S4 provided by the present invention;

[0058] Among them, Figure 4(a) is the schematic diagram of data processing; Figure 4(b) is the implementation flowchart. Detailed Embodiments

[0059] To make the above objects, features, and advantages of the present invention more apparent and understandable, the following provides a detailed description of the specific embodiments of the present invention in conjunction with the accompanying drawings. Many specific details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein.

[0060] According to one aspect of the present disclosure, a method for compiling a load spectrum applicable to high-temperature components of an aeroengine includes the following steps:

[0061] S1: In combination with the operating conditions and measured flight data, perform a thermal-mechanical multi-field coupling analysis on the evaluated high-temperature component (such as a turbine disk) to determine the life assessment region and its typical state parameters under load;

[0062] S2: Establish an equivalent conversion model between fatigue-creep loads and fatigue loads;

[0063] (1) Determine that the model architecture for load conversion processing is in the form of a second-order polynomial:

[0064]

[0065] c i is a material parameter.

[0066] (2) Determine the relationship between the material tensile strength and temperature through a material tensile test;

[0067] (3) According to the finite element calculation results, determine the stress S T corresponding to the equivalent stress at the reference temperature T0

[0068] (4) Conduct a low-cycle fatigue test. Determine the damage index and then the model parameters from the number of life cycles corresponding to different holding times under single and multi-level stress levels of combined loading;

[0069] S3: To determine the model parameters, use the state parameters calculated in step S1 as input conditions, conduct material tests (tensile, fatigue, fatigue-creep under single and combined loading), and determine the number of life cycles and damage index corresponding to each stress level and holding time;

[0070] S4: Identify the duration of the holding (constant load) of equal-value and small-amplitude cycles in the data compression process, convert them into fatigue cycles using the equivalent conversion model established in steps S2 and S3, and superimpose the fatigue cycle statistical matrix obtained from the cycle counting process to obtain the total cycle statistical matrix, and verify the life prediction accuracy.

[0071] In one embodiment of the present disclosure, the above step S1 includes the following specific steps:

[0072] S11: Determine the common and typical operating condition ranges. Generally, at least cover the operating condition points such as idle, cruise, and maximum. Taking the measured flight data of a certain type of engine as an example (in the following text, unless otherwise specified, it is this case), as shown in Table 1;

[0073] S12: Determine the boundary conditions for finite element calculation according to the actual loading conditions of the components under assessment, and perform multi-field coupling solution. According to at least one embodiment of the present disclosure, the input information for thermal-structural finite element calculation includes: material parameters, loading, constraints, thermal boundaries, algorithms. Set each operating condition point as a time sub-step and perform transient analysis.

[0074] Table 1 Calculation parameters of high-pressure turbine disk under typical conditions

[0075]

[0076] Preferably, multiple fields such as thermal-structural-acoustic-vibration-flow can be coupled simultaneously to simulate the loading such as centrifugal force, thermal stress, aerodynamic impact, and rotor vibration to the greatest extent.

[0077] In one embodiment of the present disclosure, as Figure 2 shown, the above step S2 includes the following specific steps:

[0078] S21: Based on the generalized fatigue-creep load equivalent conversion theory, determine the load processing method for high-temperature conditions;

[0079] It is considered that the damage process of the material is non-linear, and the damage values generated by each level of load under complex loading are cumulated non-linearly. The generalized fatigue-creep load equivalent conversion theory holds that: 1) If a group of fatigue-creep composite (holding time t B ≠0) loading and another group of pure fatigue (t B =0) loading with the same peak-valley value contribute equal damage, that is:

[0080]

[0081] Here, small-amplitude cycles below a certain threshold are also regarded as holding; specifically, "small amplitude" can be defined by less than a certain rotational speed or stress percentage threshold. The threshold is determined by the change trend of the total damage value when removed by different amplitudes, such as 0.3%. According to a large number of statistics, small cycles are mainly concentrated in the rotational speed range where both the peak and valley values are above 80%, which is the area where the engine is frequently used and the throttle lever moves slightly more; there is also a part in the idle speed range; the range below the idle speed can be ignored.

[0082] S22: Determine the model architecture for load conversion processing;

[0083] From the deformation of the formula in S21, the equivalent conversion ratio of fatigue load and fatigue-creep composite load can be obtained Definition:

[0084]

[0085] where a and b are the damage indices under pure fatigue and fatigue-creep combined loading respectively; N f , are the corresponding lives of the two, and the above parameters are all obtained from low-cycle fatigue (fatigue-creep) tests. Corresponding to a certain working condition point (stress level S, hold time t B , temperature T), the meaning of B is that when t B ≠0, the damage contributed by 1 cycle is equivalent to cycles when t

[0086] S23: Combine the actual application conditions and make adaptive simplification and adjustment to the model architecture;

[0087] According to the general stress criterion, the fatigue damage caused by the stress level at temperature T to the material depends on the ratio of the stress S T to the tensile strength of the material at temperature T. Therefore, the stress S T corresponding to the temperature T of each working condition point in the solution result of step S1 can be converted into the equivalent stress

[0088]

[0089] at a certain reference temperature T0. In this way, the definition formula of the equivalent conversion ratio can be simplified to a form containing only two parameters:

[0090]

[0091] The left side of the above formula can be determined by polynomial series approximation (Weierstrass approximation theorem), and the coefficients are obtained from the least squares regression test data. Considering both the fitting accuracy and the solving difficulty, a second-order polynomial form is selected:

[0092]

[0093] c i is a material parameter.

[0094] In an embodiment of the present disclosure, the above step S3 includes the following specific steps:

[0095] S31: Conduct tensile tests on the material at different temperatures; Fit the relationship between the tensile strength and temperature of the material at different temperatures from the tensile tests at different temperatures. Taking a nickel-based superalloy material as an example:

[0096]

[0097] Determine the equivalent stress at the reference temperature corresponding to the stress at different temperatures:

[0098]

[0099] According to the actual working temperature of the engine in the application case and combined with the finite element analysis results, take the reference temperature T0 at the root of the rear seal labyrinth teeth of the turbine disk as 550 °C.

[0100] S32: Conduct low-cycle fatigue (fatigue-creep) tests under single and combined loadings; use the finite element calculation results of the reference temperature T0 and its corresponding equivalent stress As input conditions, the equivalent stresses at the reference temperature of 550 °C for 4 typical working condition points are 1066 MPa, 1144 MPa, 1244 MPa, and 1287 MPa respectively. Conduct low-cycle fatigue (fatigue-creep) tests under single and combined loadings. Control the test waveform as a triangular / trapezoidal wave, and the hold time does not exceed the maximum hold time in the load history.

[0101] S33: Determine the model parameters using the test data; use the life cycle data of the single and combined loading tests to determine the damage index of each level of load by the non-linear damage accumulation method, and substitute it into the definition formula of the equivalent conversion ratio of the fatigue load and the fatigue-creep composite load to determine the model parameters and complete the modeling, as Figure 3 shown;

[0102] In an embodiment of the present disclosure, as shown in FIGS. 4(a) and 4(b), the above step S4 includes the following specific steps:

[0103] S41: Equivalent point processing. Before extracting the peak and valley values in the rainflow counting process, identify the duration of the equivalent load (hold time), call the model to convert it into a fatigue cycle and compress it into one point in the original load-time history;

[0104] S42: Small amplitude cycle processing. After extracting the peak and valley values, identify the peak and valley values of the small amplitude cycles in the range above the idle speed, identify the positions of the cycle peak and valley values in the original history to calculate the hold time between them, and convert them into fatigue cycles by the model; "small amplitude" can be defined as less than a certain rotational speed or stress percentage threshold, and the threshold is determined by the change trend of the total damage value when removing different amplitudes, such as 0.3%. The small cycles are mainly concentrated in the rotational speed range where both the peak and valley values are above 80%, which is exactly the area where the engine is frequently used and the throttle lever moves slightly more; there is also a part in the idle speed range; the range below the idle speed can be ignored.

[0105] S43: Completion of statistics to obtain the total cycle statistical matrix; superimpose the asymmetric stress cycle statistical matrix obtained in the cycle extraction step on the converted fatigue cycle statistical matrix obtained in the previous step to obtain the total cycle statistical matrix. Select 591 groups of flight data of a certain type of aero-engine, with a total working time of 532.3 hours. Use the traditional rain-flow method (T-RC) and the method disclosed in this application (I-RC) to statistically analyze the stress cycle spectrum in the life assessment area, as shown in Table 2. The total cycle numbers obtained by the two methods are 35508 and 65574 respectively.

[0106] Table 2 Equivalent stress cycle statistics of high-pressure turbine disk

[0107]

[0108]

[0109] S44: Verify the accuracy of life prediction. Using the life-time fraction prediction method, the damage values of the T-RC and I-RC methods obtained from Table 2 are 0.0988 and 0.3935 respectively. Calculation shows that the damage considered by conversion of the equivalent points in the local speed range is equivalent to 61.34% of the pure fatigue cycle (T-RC result), while the damage introduced by the full-condition equivalent value and small-amplitude load treatment in the method disclosed in this application is equivalent to 298.25% of the pure fatigue cycle. The remaining lives predicted by the two methods are 4857.2 h and 822.0 h respectively; the total lives are 5388.5 h and 1354.4 h respectively. Currently, the given life of the high-pressure turbine disk of this type of engine is 1250 h. From this, the prediction deviations calculated by the three methods are: 331.08% and 8.35% respectively.

[0110] It can be seen that the life prediction result of the load spectrum compilation method applicable to high-temperature components of aero-engines in the present invention is accurate and significantly optimized; it fully verifies that the load treatment under high-temperature conditions must consider the fatigue-creep coupling damage during the hold time; the large error obtained by the traditional rain-flow method is due to the neglect or insufficient consideration of this part of the load, and it contributes most of the total damage (74.89% in the embodiment of the present invention). The present invention is applicable to the structural integrity research of components with extreme and complex service environments such as key components at the hot end of the engine. On the premise of known flight data and not-too-severe test conditions, it can give sufficiently true and reliable load treatment results; and it has sufficient reference value for other fields with requirements for high-temperature condition load spectrum compilation.

[0111] Other embodiments of the present disclosure will be readily apparent to those skilled in the art in view of the specification and practice of the disclosure herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include known common general knowledge or conventional technical means in the technical field not disclosed in the present disclosure. The specification and examples are only to be considered as exemplary, and the true scope and spirit of the present disclosure are indicated by the appended claims.

[0112] It should be understood that the present disclosure is not limited to the exact structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present disclosure should be limited by the appended claims.

Claims

1. A method for compiling a load spectrum applicable to high-temperature components of an aero-engine, characterized in that, The method for compiling a load spectrum applicable to high-temperature components of an aeroengine includes the following steps: Step 1: Combine the operating conditions and measured flight data to conduct thermo-mechanical multi-field coupling analysis on the evaluated high-temperature components, and determine the life assessment area and its typical state parameters under load; Step 2: Establish an equivalent conversion model between fatigue-creep load and fatigue load; Step 3: To determine the model parameters, use the calculated state parameters as input conditions, conduct material tests, and determine the number of life cycles and damage index corresponding to each stress level and hold time; Step 4: Identify the duration of equal-value and small-amplitude cycles in the data compression process, convert them into fatigue cycles using the established equivalent conversion model, and superimpose the fatigue cycle statistical matrix obtained from the cycle counting process to obtain the total cycle statistical matrix, and verify the life prediction accuracy; In the above Step 2, the establishment of the equivalent conversion model between fatigue-creep load and fatigue load includes the following steps: The first step: Determine that the model architecture for load conversion processing is in the form of a second-order polynomial: c i is the material parameter; represents the equivalent conversion ratio of fatigue load and fatigue-creep composite load; The second step: Determine the relationship between the material tensile strength and temperature through material tensile tests; Step 3: Determine the stress S at each temperature T based on the finite element calculation results T The equivalent stress corresponding to the reference temperature T0 The fourth step: Conduct low-cycle fatigue tests, and determine the damage index and then the model parameters based on the number of life cycles corresponding to different hold times under single and multi-level stress levels of combined loading.

2. The method for compiling a load spectrum applicable to high-temperature components of an aero-engine according to claim 1, characterized in that The above-mentioned material tests include: tensile tests, fatigue tests, and fatigue-creep tests under single and combined loading.

3. The load spectrum compilation method applicable to high-temperature components of an aero-engine according to claim 1, characterized in that The specific content of the above Step 1 includes the following steps: The first step: Determine the common and typical operating condition intervals; The second step: Determine the boundary conditions for finite element calculation according to the actual load conditions of the component under assessment, and conduct multi-field coupling solution.

4. The method for compiling a load spectrum applicable to high-temperature components of an aeroengine according to claim 1, characterized in that The specific content of determining that the model architecture for load conversion processing is in the form of a second-order polynomial includes the following steps: The first step: Based on the generalized equivalent conversion theory of fatigue-creep load, determine the load processing method for high-temperature conditions; According to the equivalent conversion theory of fatigue-creep load, if the damage contributed by a group of fatigue-creep composite loading is equal to that of another group of pure fatigue loading with the same peak-valley value, that is: The holding time t for the fatigue-creep composite B ≠0, and the t for pure fatigue B = 0; The second step: Determine the model architecture for load conversion processing; According to the transformation of formula (2), the equivalent conversion ratio of fatigue load and fatigue-creep composite load can be obtained The definition is as follows: where a and b are the damage indices under pure fatigue and fatigue-creep composite loading respectively; N f , are the corresponding lives of the two, and the above parameters are all obtained from low-cycle fatigue tests; corresponding to a certain working condition point, the meaning of B is that when t B ≠0, the damage contributed by 1 cycle is equivalent to cycles when t B =0; the said certain working condition point includes stress level S, hold time t B , and temperature T. The third step: Combine the actual application conditions to conduct adaptive simplification and adjustment on the model architecture; According to the general stress criterion, the fatigue damage caused by the stress level at temperature T to the material depends on the stress S T and the tensile strength of the material at temperature T The ratio; therefore, the stress S corresponding to the temperature T of each working condition point in the solution result T is converted into an equivalent stress at a certain reference temperature T0 Equivalent conversion ratio The defining formula can be simplified to a form that only contains two parameters: The left side of the above formula can be determined by polynomial series approximation, and the coefficients are obtained from the least squares regression test data; considering both the fitting accuracy and the solution difficulty, select the second-order polynomial form: c i is a material parameter.

5. The method for compiling a load spectrum applicable to high-temperature components of an aero-engine according to claim 1, wherein The specific content of Step 3 includes the following: The first step: Conduct material tensile tests at different temperatures; fit the relationship between the material tensile strength and temperature at different temperatures from the tensile tests at different temperatures; Step 2: Conduct low-cycle fatigue tests under single and combined loading; use the reference temperature T0 and its corresponding equivalent stress obtained from the finite element calculation results as input conditions; Step 3: Determine the model parameters using test data; determine the damage indices of each level of load by the non-linear damage accumulation method using the life cycle data of the separate and combined loading tests, and substitute them into the definition formula of the equivalent conversion ratio of the fatigue load and the fatigue-creep composite load to determine the model parameters and complete the modeling.

6. The method for compiling a load spectrum applicable to high-temperature components of an aero-engine according to claim 1, wherein The specific content of Step 4 includes the following: The first step: Equal-value point processing; Before extracting the peak-valley values in the rainflow counting process, identify the duration of equal-value loads, call the model to convert them into fatigue cycles and compress them into one point in the original load-time history; The second step: Small-amplitude cycle processing; After extracting the peak-valley values, identify the peak-valley values of small-amplitude cycles in the interval above the idle speed, identify the positions of the cycle peak-valley values in the original history to calculate the hold time between them, and convert them into fatigue cycles by the model; The small amplitude is defined as less than a certain rotational speed or stress percentage threshold, and the threshold is determined by the change in the decreasing trend of the total damage value when removing different amplitudes; Step 3: Complete the statistics; Obtain the total cycle statistical matrix. Superimpose the asymmetric stress cycle statistical matrix obtained in the cycle extraction step on the converted fatigue cycle statistical matrix obtained in the previous step to obtain the total cycle statistical matrix; Step 4: Verify the accuracy of life prediction; Use the life-time fraction prediction method to obtain the damage values of the T-RC and I-RC methods.

7. A computer-readable storage medium stores a computer program. When the computer program is executed by a processor, the processor is caused to execute the load spectrum compilation method for high-temperature components of an aero-engine according to any one of claims 1-6.

8. An information data processing terminal, characterized in that, The information data processing terminal includes a memory and a processor. The memory stores a computer program. When the computer program is executed by the processor, the processor is caused to execute the load spectrum compilation method for high-temperature components of an aero-engine according to any one of claims 1-6.

9. An aeroengine, characterized in that, The aero-engine implements the load spectrum compilation method for high-temperature components of an aero-engine according to any one of claims 1-6.

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