Method and system for evaluating creep damage of hot end component of gas turbine engine

Abstract

The invention discloses a method and a system for evaluating creep damage of a hot-end component of a gas turbine engine, and relates to the technical field of performance detection of the hot-end component of the gas turbine engine. The method comprises the following steps that time-varying load information of a dangerous area of a hot end component of the gas turbine engine is obtained according to the real-time running state of the gas turbine engine; carrying out online cycle counting on the time-varying load information of the dangerous area of the hot end component; and performing creep damage evaluation on the dangerous area of the hot part based on the strain energy density dissipation model. By adopting the creep damage assessment method based on the strain energy density dissipation model and combining the characteristics of fatigue-creep interaction, the influence of complex factors such as stress relaxation and temperature fluctuation can be comprehensively captured, the accuracy of creep damage calculation is greatly improved, the delay of a traditional offline assessment method is overcome, and the application range is wider.

Description

Technical Field

[0001] The present invention relates to the technical field of gas turbine blade performance detection, and in particular to a method and system for evaluating creep damage of hot end components of a gas turbine engine. Background Art

[0002] As one of the most critical and complex components of gas turbines or aircraft engines, hot end components serve under extreme conditions and withstand the interactive reciprocating effects of multiple loads. They have a high failure rate. The service life of hot end components directly affects the economy and stability of gas turbine or aircraft engine operation.

[0003] Creep damage is one of the most common damage modes for hot-end components of gas turbines or aircraft engines. It is a phenomenon in which a solid material maintains constant stress at a certain temperature (a temperature exceeding 0.3 times the melting point of the material) while increasing strain over time. Fatigue and creep often occur together, and there is a complex interaction between the two. Fatigue damage causes fatigue cracks to initiate and propagate on the surface of the material, while creep damage causes dislocations and slip within the material to produce grain boundary holes. When fatigue cracks and creep grain boundary holes meet, they may promote each other and cause accelerated material failure. They may also make the stress distribution more uniform, hindering crack propagation and thus extending the life. In the existing technology, fatigue tests or creep tests are often performed separately. Therefore, it is very necessary to decouple this complex interaction and perform separate strength verification when assessing damage.

[0004] Furthermore, the maintenance strategy for hot-end components of gas turbines or aircraft engines consists of two phases: post-event maintenance and scheduled preventive maintenance. Post-event maintenance not only increases the operational risk of gas turbines or aircraft engines but can also lead to higher repair costs due to repair failures. Scheduled maintenance can lead to over-repair or disrepair of hot-end components, resulting in poor economic efficiency and reduced safety. Online damage monitoring and remaining life prediction of hot-end components of gas turbines or aircraft engines based on operating conditions can effectively address these issues.

[0005] Existing patent CN117171900A discloses a method for evaluating the creep life of aircraft engine turbine blades. This patent focuses on damage assessment under the action of fatigue or creep alone, and usually fails to fully consider the impact of the interaction between the two on material damage under high-temperature conditions. This results in poor accuracy of existing evaluation results under complex load conditions.

[0006] Existing patent CN117577242A discloses a method for optimizing a creep fatigue life prediction model for metal materials. This patent has a long calculation cycle, making it difficult to achieve online real-time monitoring and unable to promptly reflect damage changes in the equipment during actual operation.

[0007] In summary, the above two existing patents do not solve the problem of evaluating and detecting the interactive damage of hot end components under fatigue and creep in the prior art. Summary of the Invention

[0008] Based on the above technical problems, the present invention proposes a method and system for evaluating creep damage of hot end components of a gas turbine engine, which solves the problem of evaluating and detecting interactive damage of hot end components under fatigue and creep in the prior art.

[0009] To achieve the above objectives, the present invention proposes a method and system for assessing creep damage in hot end components of a gas turbine engine. The specific technical solution is as follows:

[0010] A method for evaluating creep damage of a hot end component of a gas turbine engine comprises the following steps:

[0011] Obtain the time-varying load information of the hazardous area of ​​the hot end components of the gas turbine engine according to its real-time operating status;

[0012] Online cycle counting of time-varying load information in hazardous areas of hot end components;

[0013] Creep damage assessment of hazardous areas of thermal components is performed based on the strain energy density dissipation model (SEDE).

[0014] Furthermore, the load information includes temperature load, stress load, plastic strain load, total strain load and time load.

[0015] Furthermore, the online cycle counting of the time-varying load information of the hazardous area of ​​the hot end component includes:

[0016] Identify stress extreme values ​​and eliminate invalid amplitudes based on time-varying load information;

[0017] The load data is cycle counted based on the four-point rain flow rule to extract the amplitude, mean and number of stress cycles;

[0018] According to the time information of the stress cycle, the corresponding temperature data is traversed and the stress and temperature information are integrated.

[0019] Furthermore, when counting cycles of load data based on the four-point rain flow rule, full cycles and half cycles are distinguished.

[0020] Furthermore, the creep damage assessment includes:

[0021] Calculate the creep strain energy density at a certain tension and holding moment within the identified stress cycle;

[0022] The creep strain energy density dissipation rate at a certain tensile and load-holding moment in the identified stress cycle is obtained by differentiating the load-holding time t.

[0023] Establish creep failure strain energy density function;

[0024] Calculate the creep damage within the identified stress cycles.

[0025] Furthermore, the creep strain energy density is

[0026]

[0027] Among them, w c (t) is the creep strain energy density, σ max is the maximum stress within the identified stress cycle, σ m is the average stress of the identified stress cycle, σ(t) is the stress relaxation response during the pull-hold stage of the identified stress cycle, E is the elastic modulus, and t is the time load.

[0028] Furthermore, the average stress σ of the identified stress cycle m for

[0029] The stress relaxation response σ(t) during the tension-holding stage of the identified stress cycle is:

[0030] σ(t)=σ max -(A·logΔε p +B)·log(1+t)

[0031] Among them, Δε p is the plastic strain load, A and B are fitting coefficients related to material properties.

[0032] Furthermore, in the creep strain energy density w c (t) is derived from the holding time t to obtain the creep strain energy density dissipation rate for

[0033]

[0034] in, is the stress relaxation response during the tension-holding stage of the identified stress cycle,

[0035]

[0036] Furthermore, the creep failure strain energy density function is

[0037]

[0038] Where T is the characteristic temperature within the identified stress cycle, φ is the strain energy density coefficient fitted by the uniaxial tensile creep test; n lStrain energy density exponent fitted for uniaxial tension creep test.

[0039] Furthermore, the creep damage within the identified stress cycle is

[0040]

[0041] Among them, t h is the duration of the pull-up hold in the identified cycle, w f,crit The creep failure strain energy density platform value corresponding to creep damage.

[0042] The present invention also proposes a gas turbine engine hot end component creep damage assessment system for implementing the above-mentioned gas turbine engine hot end component creep damage online assessment method. The system includes a load information acquisition module, a cycle counting module and a damage assessment module. The output end of the load information acquisition module is connected to the input end of the cycle counting module, and the output end of the cycle counting module is connected to the input end of the damage assessment module.

[0043] Furthermore, the load information acquisition module includes a data acquisition unit and a data drive unit. The data acquisition unit is used to obtain the operating data of the gas turbine engine in real time. The data drive unit is equipped with a data drive model. The data drive model uses the operating data of the gas turbine engine as input and outputs time-varying load information of the hazardous area of ​​the hot end component.

[0044] The cycle counting module includes an extreme value identification and elimination unit, a rain flow counting unit, and a temperature information association unit. The extreme value identification and elimination unit is used to identify stress extreme values ​​and eliminate invalid amplitudes in load information. The rain flow counting unit performs cycle counting on load data based on a four-point online rain flow method. The temperature information association unit is used to integrate stress and temperature information.

[0045] The damage assessment module includes a creep strain energy density calculation unit, a creep strain energy density dissipation rate calculation unit, a creep damage calculation unit and a damage assessment unit.

[0046] Based on the above technical solutions of the present invention, the beneficial effects of the present invention are as follows:

[0047] 1. This invention proposes a method and system for assessing creep damage in hot-end components of a gas turbine engine. This method employs a creep damage assessment method based on a strain energy density dissipation model, combined with the characteristics of fatigue-creep interaction. This method can comprehensively capture the influence of complex factors such as stress relaxation and temperature fluctuations. This solution significantly improves the accuracy of creep damage calculations, making the assessment results more realistic.

[0048] 2. The present invention proposes a method and system for assessing creep damage in hot-end components of a gas turbine engine. This overcomes the latency inherent in traditional offline assessment methods through real-time acquisition of operating status parameters and load information and online cycle counting. This enables the equipment to obtain immediate damage information during actual operation, thereby enabling timely monitoring of the equipment status. This provides an efficient means of damage monitoring for operating gas turbines, aircraft engines, and other equipment.

[0049] 3. This invention proposes a method and system for creep damage assessment of gas turbine engine hot-end components. Using an online cycle counting method, the system fully couples random loads with temperature fluctuations. This method enables real-time identification of cyclic stresses and recording of temperature information under actual operating conditions, adapting to a variety of complex loading conditions. Therefore, this technical solution is suitable for component damage assessment under conditions such as high temperature, high pressure, and alternating loads, extending its applicability to a wider range of conditions.

[0050] 4. The present invention proposes a method and system for assessing creep damage in hot-end components of a gas turbine engine. Through real-time and accurate creep damage monitoring, the system can effectively predict the remaining life of the equipment, reduce the risk of over-repair or disrepair, and further optimize maintenance strategies, which can significantly reduce equipment maintenance costs while improving the safety and economy of equipment operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The accompanying drawings, which constitute part of the present invention, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0052] Figure 1 1 is a flow chart of a method for evaluating creep damage of hot end components of a gas turbine engine proposed by the present invention;

[0053] Figure 2 This is a partial flow diagram of a method for evaluating creep damage of hot end components of a gas turbine engine proposed by the present invention;

[0054] Figure 3 This is a flow chart of online cycle counting in a creep damage assessment method for hot end components of a gas turbine engine proposed by the present invention;

[0055] Figure 4 This is a schematic diagram of the framework of a creep damage assessment system for hot end components of a gas turbine engine proposed in the present invention. DETAILED DESCRIPTION

[0056] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0057] The present invention is further described in detail below with reference to specific examples. These examples should not be construed as limiting the scope of protection claimed in the present invention.

[0058] In order to solve the problem of evaluating and detecting interactive damage of hot end components under fatigue and creep in the prior art, the present invention proposes a creep damage evaluation method and system for hot end components of a gas turbine engine.

[0059] Example 1

[0060] To achieve the above objectives, this embodiment proposes a method for evaluating creep damage of hot end components of a gas turbine engine. Figure 1 As shown, the method includes the following steps:

[0061] Obtain the time-varying load information of the hazardous area of ​​the hot end components of the gas turbine engine according to its real-time operating status;

[0062] Online cycle counting of time-varying load information in hazardous areas of hot end components;

[0063] Creep damage assessment of hazardous areas of thermal components is performed based on the strain energy density dissipation model (SEDE).

[0064] See Figure 2 As shown, the above-mentioned implementation process of obtaining the time-varying load information of the hazardous area of ​​the hot end component of the gas turbine engine according to the real-time operating status of the gas turbine engine is as follows:

[0065] Ⅰ. Obtain the operating status parameters of the gas turbine engine in real time;

[0066] Specifically, a variety of sensors and data acquisition devices are used to obtain real-time operating parameters of gas turbine engines. For gas turbines, temperature, pressure, and vibration sensors are placed in key locations such as the compressor, combustion chamber, and turbine. For aircraft engines, these sensors are placed in key locations such as the turbine blades and compressor shaft. Data acquisition cards and embedded systems are used to collect data in real time. Operating parameters include mechanical parameters such as speed and vibration, thermodynamic parameters such as temperature and pressure, aerodynamic parameters such as airflow velocity and pressure distribution, and electrical parameters such as voltage and current.

[0067] In the actual operation of a gas turbine engine, the measured parameters of the sensor may not be sufficient to meet the real-time operating state parameters required for model calculation. Therefore, a performance model can be built based on thermodynamic principles to supplement the real-time operating state parameters of the gas turbine engine.

[0068] II. Obtain the time-varying load information of the hazardous area of ​​the hot end components through the data-driven model based on the real-time operating status parameters.

[0069] Specifically, numerical calculations or experiments are used to identify the hazardous areas of the hot-end components of a gas turbine engine under different operating conditions. These hazardous areas are those that experience the greatest stress, highest temperature, or most severe corrosion during operation. These areas are typically critical blade locations, such as the blade root, blade tip, leading edge, and trailing edge. The numerical calculation method involves first using CAD software to create a three-dimensional geometric model of the hot-end components, simplifying the complex structure while retaining key features (such as cooling holes and blade profiles). The geometric model is then meshed using mesh generation software, with mesh refinement performed in hazardous areas (such as the blade root, leading edge, and trailing edge). Boundary conditions (such as temperature, pressure, and speed) are then set based on the engine's operating conditions (such as takeoff, cruise, and landing), and aerodynamic, thermal, and centrifugal loads are applied. Finally, finite element analysis software is used to analyze the stress, strain, and temperature fields, identifying areas of high stress, high strain, and high temperature, which are then marked as hazardous areas.

[0070] The experimental method involves first designing an experimental plan to simulate engine operating conditions, selecting experimental equipment, and then placing strain gauges, thermocouples, and other sensors on the surface of the hot end components to measure stress, strain, and temperature distribution. Optical measurement techniques are then used to obtain full-field strain data. Finally, the experimental data is analyzed to identify the hazardous area. This data can be compared with the results of numerical calculations to verify the accuracy of the aforementioned model.

[0071] Using finite element simulation and computational fluid dynamics methods, the corresponding relationship between the operating parameters of a gas turbine engine under different operating conditions and the load information in the hazardous area of ​​the hot end components is determined. First, finite element analysis is performed for different operating conditions (such as speed, temperature, and pressure) to extract stress, strain, and temperature data in the hazardous area. The load information under different operating conditions is organized into load spectra, generating stress-time and temperature-time curves. CFD software is then used to establish an engine flow field model, simulating the flow through the compressor, combustor, and turbine. The pressure distribution and heat flux density on the surface of the hot end components are extracted. The aerodynamic loads are input as boundary conditions into the finite element model, and a fluid-structure coupling analysis is performed. The effects of aerodynamic and thermal loads on the structure are considered, and the corresponding relationship between the operating parameters (such as speed, temperature, and pressure) and the hazardous area load information is generated. The finite element and CFD analysis results are then organized into a structured dataset, including the operating parameters and hazardous area load information.

[0072] Using the correspondence between operating state parameters and load information as a data set, a data-driven model is built to predict the load information from operating state parameters to hazardous area. First, data preprocessing is performed to remove outliers and noise data and interpolate or delete missing data. Input and output data are normalized and the data set is divided into training set, validation set, and test set. Then, a machine learning model is selected and model training is performed; mean square error (MSE), mean absolute error (MAE), coefficient of determination (R 2 ) and other indicators to evaluate model performance; the trained model is deployed to the online evaluation system.

[0073] The data-driven model is used to predict the time-varying load information of the dangerous area of ​​the hot end component of the gas turbine engine through the real-time operating status parameters obtained in the above Ⅰ. The time-varying load information includes temperature T, stress σ, plastic strain Δε pa , total strain Δε a and time t.

[0074] See Figure 3 As shown, the above-mentioned implementation process of online cycle counting of the time-varying load information of the hazardous area of ​​the hot end component is as follows:

[0075] Specifically, according to the time-varying load information of the dangerous area of ​​the hot end component (including temperature T, stress σ, plastic strain Δε pa , total strain Δε a The stress peaks and valleys are extracted from the load data using a peak-valley detection algorithm, ensuring that only alternating extreme points are included in the data. Invalid cycles with small amplitudes are removed based on a set amplitude threshold. For example, cycles with amplitudes below a certain percentage threshold (such as 0.3%) are removed. Before rainflow counting, the duration of equivalent loads is identified and converted into fatigue cycles, which are then compressed into single points to simplify the data.

[0076] The extracted extreme value data is reconstructed to ensure that the load time series begins and ends with extreme values, avoiding irrational data during the splicing process. Full cycles and half cycles are distinguished according to the four-point rainflow method. Assuming the stress values ​​of four consecutive extreme value points read from the extreme value data stack are σ1, σ2, σ3, and σ4, let Δσ1 = |σ1-σ2|, Δσ2 = |σ2-σ3|, and Δσ3 = |σ3-σ4|. If Δσ2 < Δσ1 and Δσ2 < Δσ3, then Δσ2 is considered to constitute a full cycle. Points σ2 and σ3 are eliminated, while points σ1 and σ4 are retained. New stress flow points are read backward and re-identified. Otherwise, Δσ1 is considered to constitute a half cycle. Point σ1 is eliminated, while points σ2, σ3, and σ4 are retained. New stress flow points are read backward and re-identified.

[0077] The time information of the stress cycle is associated with the temperature data to ensure the accuracy of the temperature information corresponding to each cycle. During the pull-load duration of each stress cycle, the temperature information is traversed and the temperature changes are recorded. The stress cycle and the corresponding temperature information are integrated to form a complete load spectrum, providing data support for subsequent evaluation.

[0078] The implementation process of creep damage assessment of hazardous areas of hot end components based on the strain energy density dissipation model is as follows:

[0079] Specifically, first calculate the average stress σ of the identified stress cycle m , mean stress σ m for

[0080]

[0081] Among them, σ max is the maximum stress in the identified stress cycle, σ min is the minimum stress in the identified stress cycle.

[0082] Then calculate the creep strain energy density w at a certain tension and holding moment within the identified stress cycle c (t), creep strain energy density w c (t) is

[0083]

[0084] Where E is the elastic modulus, σ(t) is the stress level at a certain moment in the tension-load-holding stage of the identified stress cycle, which is essentially the stress relaxation response in the tension-load-holding stage.

[0085] σ(t)=σ max -(A·logΔε p +B)·log(1+t)

[0086] Among them, Δε p is the plastic strain, A and B are constants related to material properties.

[0087] In the creep strain energy density w c (t), the creep strain energy density dissipation rate at a certain tensile and loading moment in the identified stress cycle is obtained by differentiating the loading time t. for

[0088]

[0089] Where σ(t) is the stress relaxation rate at a certain moment in the tension and holding stage of the identified stress cycle.

[0090]

[0091] Creep failure strain energy density function for

[0092]

[0093] Where T is the characteristic temperature within the identified stress cycle, φ is the strain energy density coefficient fitted by the uniaxial tensile creep test; n l Strain energy density exponent fitted for uniaxial tension creep test.

[0094] Finally, the creep damage within the identified stress cycle is calculated.

[0095]

[0096] Among them, t h is the duration of the pull-up hold in the identified cycle, w f,crit The creep failure strain energy density platform value corresponding to creep damage.

[0097] When the creep test stress level is high, a platform value of the failure strain energy density appears, and the platform value is determined as w f,crit The current creep damage value is obtained by summing the creep damage in all cycles from the start time to the current time. It is then compared with the threshold (taken as 1) to determine whether the current creep damage life has been reached.

[0098] Example 2

[0099] This embodiment provides a system for evaluating creep damage of hot end components of a gas turbine engine. The system is used to implement a method for evaluating creep damage of hot end components of a gas turbine engine proposed in the above embodiment 1. Figure 4 As shown, the system includes a load information acquisition module, a cycle counting module and a damage assessment module. The output end of the load information acquisition module is connected to the input end of the cycle counting module, and the output end of the cycle counting module is connected to the input end of the damage assessment module.

[0100] Among them, the load information acquisition module includes a data acquisition unit and a data driving unit. The data acquisition unit is used to obtain the operating data of the gas turbine engine in real time. A data-driven model is built in the data driving unit. The data-driven model uses the operating data of the gas turbine engine as input and outputs time-varying load information of the dangerous area of ​​the hot end component.

[0101] The cycle counting module includes an extreme value identification and elimination unit, a rain flow counting unit, and a temperature information association unit. The extreme value identification and elimination unit is used to identify stress extremes and eliminate invalid amplitudes in time-varying load information; the rain flow counting unit counts the cycles of load data based on the four-point online rain flow method and extracts the amplitude, mean, and number of stress cycles; the temperature information association unit is used to traverse the corresponding temperature data according to the time information of the stress cycle and integrate the stress and temperature information.

[0102] The damage assessment module includes a creep strain energy density calculation unit, a creep strain energy density dissipation rate calculation unit, a creep damage calculation unit and a damage assessment unit.

[0103] The aforementioned method and system for assessing creep damage in hot-end components of a gas turbine engine, proposed in this invention, utilizes a creep damage assessment method based on the strain energy density dissipation (SEDE) model. By incorporating the characteristics of fatigue-creep interaction, this method comprehensively captures the influence of complex factors such as stress relaxation and temperature fluctuations. Compared to existing technologies, this solution significantly improves the accuracy of creep damage calculations, making assessment results more realistic. By real-time acquisition of operating parameters and load information and online cycle counting, this approach overcomes the latency inherent in traditional offline assessment methods, enabling real-time damage information to be obtained during actual operation, enabling timely monitoring of equipment status. This provides an efficient damage monitoring method for operating gas turbine engine equipment. Furthermore, the online cycle counting method fully couples random loads with temperature fluctuations, enabling real-time identification of cyclic stresses and recording of temperature information under actual operating conditions. This adapts to a wide range of complex loading conditions and offers a wider range of applications. Real-time and accurate creep damage monitoring effectively predicts the remaining life of equipment, reduces the risk of over-repair or disrepair, and optimizes maintenance strategies, significantly reducing equipment maintenance costs while improving the safety and economic efficiency of equipment operation.

[0104] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

[0105] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0106] The logic and / or steps represented in the flowchart or otherwise described herein may be considered, for example, as an ordered list of executable instructions for implementing logical functions, and may be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device).

[0107] It should be understood that various parts of the present invention can be implemented using hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application-specific integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0108] It should be noted that, in the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

Claims

1. A method for evaluating creep damage of hot end components of a gas turbine engine, characterized in that: The method comprises the following steps: Obtain the time-varying load information of the hazardous area of ​​the hot end components of the gas turbine engine according to its real-time operating status; Online cycle counting of time-varying load information in hazardous areas of hot end components; Creep damage assessment of hazardous areas of thermal components is performed based on the strain energy density dissipation model (SEDE).

2. The method for evaluating creep damage of hot end components of a gas turbine engine according to claim 1, wherein: The load information includes temperature load, stress load, plastic strain load, total strain load and time load.

3. The method for evaluating creep damage of hot end components of a gas turbine engine according to claim 2, wherein: The online cycle counting of the time-varying load information of the hazardous area of ​​the hot end component comprises: Identify stress extreme values ​​and eliminate invalid amplitudes based on time-varying load information; The load data is cycle counted based on the four-point rain flow rule to extract the amplitude, mean and number of stress cycles; According to the time information of the stress cycle, the corresponding temperature data is traversed and the stress and temperature information are integrated.

4. The method for evaluating creep damage of hot end components of a gas turbine engine according to claim 3, wherein: When counting cycles of load data based on the four-point rain flow rule, full cycles and half cycles are distinguished.

5. The method for evaluating creep damage of hot end components of a gas turbine engine according to claim 3, wherein: The creep damage assessment includes: Calculate the creep strain energy density at a certain tension and holding moment within the identified stress cycle; The creep strain energy density dissipation rate at a certain tensile and load-holding moment in the identified stress cycle is obtained by differentiating the load-holding time t. Establish creep failure strain energy density function; Calculate the creep damage within the identified stress cycles.

6. The method for evaluating creep damage of hot end components of a gas turbine engine according to claim 5, wherein: The creep strain energy density is Among them, w c (t) is the creep strain energy density, σ max is the maximum stress within the identified stress cycle, σ m is the average stress of the identified stress cycle, σ(t) is the stress relaxation response during the pull-hold stage of the identified stress cycle, E is the elastic modulus, and t is the time load.

7. The method for evaluating creep damage of hot end components of a gas turbine engine according to claim 6, wherein: The average stress σ of the identified stress cycle m for The stress relaxation response σ(t) during the tension-holding stage of the identified stress cycle is: in, is the plastic strain load, A and B are fitting coefficients related to material properties.

8. The method for evaluating creep damage of a hot end component of a gas turbine engine according to claim 6, wherein: In the creep strain energy density w c (t) is derived from the holding time t to obtain the creep strain energy density dissipation rate for in, is the stress relaxation response during the tension-holding stage of the identified stress cycle, 9. The method for evaluating creep damage of hot end components of a gas turbine engine according to claim 8, wherein: The creep failure strain energy density function is: Where T is the characteristic temperature within the identified stress cycle, φ is the strain energy density coefficient fitted by the uniaxial tensile creep test; n l Strain energy density exponent fitted for uniaxial tension creep test.

10. The method for evaluating creep damage of hot end components of a gas turbine engine according to claim 9, wherein: The creep damage within the identified stress cycle is Among them, t h is the duration of the pull-up hold in the identified cycle, w f,crit The creep failure strain energy density platform value corresponding to creep damage.

11. A gas turbine engine hot end component creep damage assessment system, used to implement the gas turbine engine hot end component creep damage assessment method according to any one of claims 1 to 10, characterized in that: The system includes a load information acquisition module, a cycle counting module and a damage assessment module. The output end of the load information acquisition module is connected to the input end of the cycle counting module, and the output end of the cycle counting module is connected to the input end of the damage assessment module.

12. The gas turbine engine hot end component creep damage assessment system according to claim 11, characterized in that: The load information acquisition module includes a data acquisition unit and a data drive unit. The data acquisition unit is used to obtain the operating data of the gas turbine engine in real time. The data drive unit is built with a data drive model. The data drive model uses the operating data of the gas turbine engine as input and outputs time-varying load information of the hazardous area of ​​the hot end component. The cycle counting module includes an extreme value identification and elimination unit, a rain flow counting unit, and a temperature information association unit. The extreme value identification and elimination unit is used to identify stress extreme values ​​and eliminate invalid amplitudes in load information. The rain flow counting unit performs cycle counting on load data based on a four-point online rain flow method. The temperature information association unit is used to integrate stress and temperature information. The damage assessment module includes a creep strain energy density calculation unit, a creep strain energy density dissipation rate calculation unit, a creep damage calculation unit and a damage assessment unit.

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