A method and system for evaluating uncertain high-cycle fatigue of detuned blade disks

Abstract

The present invention proposes a method and system for evaluating the uncertainty high-cycle fatigue of a detuned blade disk. The method includes the following steps: determining and simulating a blade disk model comprising rotor blades and stator blades; obtaining excitation identification results of the rotor blades based on the simulated blade disk model; obtaining potential resonance points on the rotor blades based on the excitation identification results and determining the natural frequencies of the potential resonance points; obtaining detuning parameters for multiple sets of blade disks of the same specification based on the natural frequencies of the potential resonance points; obtaining detuning vibration amplitudes of the blade disks corresponding to the detuning parameters based on the multiple sets of detuning parameters; and obtaining an evaluation result of the uncertainty high-cycle fatigue of the blade disk based on the detuning vibration amplitudes. This method improves the efficiency of measuring detuning parameters, the accuracy of test measurement results, and the robustness of high-cycle fatigue judgment results.

Description

Technical Field

[0001] The present invention belongs to the technical field of engine blade disk parameter measurement, and in particular relates to a method and system for evaluating uncertainty high-cycle fatigue of a detuned blade disk. Background Art

[0002] Engine blade disks are typically equipped with vibration dampening structures. This is because resonance within the blade disk can easily lead to high-cycle fatigue failure over time. However, due to the rich excitation frequencies and dense modal frequencies of blade disks during operation, and their typical operation within a wide speed range, it is difficult to avoid all resonances. Therefore, vibration design for blade disks generally focuses on avoiding only the most damaging resonances. Vibration stress is a key parameter used to assess whether a blade disk is susceptible to high-cycle fatigue failure.

[0003] Currently, vibration stress testing can directly measure the vibration stress of blade disks. However, this test is expensive and cannot be performed during engine manufacturing, making it difficult to detect problems in advance. Therefore, unsteady flow simulation has become the mainstream method for blade disk analysis. This method simulates and measures the vibration amplitude of the blade disk to obtain the vibration stress.

[0004] However, in actual operation, due to manufacturing tolerances and service wear, the overall blade disk structure may no longer be cyclically symmetrical. Small differences in the blade disk structure can lead to significant differences in the blade disk's vibration response, localizing the blade disk's vibration, known as detuning. The energy of a detuned blade disk is concentrated on individual blades, significantly amplifying the vibration amplitude compared to a tuned blade disk, thus affecting the blade disk's vibration stress. When testing blade disks using unsteady flow field simulations, these simulations are generally based on a tuned blade disk. This assumes that each blade on the blade disk has the same structure and vibration amplitude during vibration response, without considering the impact of blade disk detuning. This can lead to significant discrepancies between test results and actual conditions. High-cycle fatigue assessment is a critical step in blade design. Due to the random nature of blade disk detuning, high-cycle fatigue performance also exhibits significant uncertainty. Therefore, determining the actual vibration level of a detuned blade disk and conducting uncertain high-cycle fatigue assessments is key to improving the accuracy of high-cycle fatigue assessments. Existing uncertainty high-cycle fatigue assessments of blade disks are difficult to accurately assess. Summary of the Invention

[0005] In response to the above problems, the present invention proposes a method and system for evaluating the uncertainty high cycle fatigue of a detuned blade disk. The method for evaluating the uncertainty high cycle fatigue of a detuned blade disk comprises the following steps:

[0006] Determine and simulate a bladed disk model consisting of rotor blades and stator blades;

[0007] obtaining an excitation identification result of the rotor blade based on the blade disk model of the simulation operation;

[0008] Based on the excitation identification result, obtaining a potential resonance point on the rotor blade, and determining a natural frequency of the potential resonance point;

[0009] Based on the natural frequency of the potential resonance point, obtaining detuning parameters of multiple groups of blade disks of the same specification;

[0010] Based on the multiple groups of detuning parameters, obtaining the detuning vibration amplitude of the blade disk corresponding to the detuning parameters;

[0011] An uncertain high cycle fatigue evaluation result of the blade disk is obtained based on the deharmonic vibration amplitude.

[0012] In some specific embodiments, the following steps are provided before obtaining the excitation identification result of the rotor blade based on the blade disk model running the simulation and determining the natural frequency of the potential resonance point:

[0013] Simulating and running the blade disk model to control the weekly time step of the rotor blades to meet the sampling frequency requirement;

[0014] The aerodynamic pressure on the rotor blades is extracted and determined, and the aerodynamic pressure on the rotor blades is controlled to periodically meet requirements.

[0015] In some specific embodiments, the weekly time step of the rotor blade rotation satisfies the following conditions:

[0016] N s >2K·max(EO i )

[0017] Among them, N s is the time step per week when the rotor blade rotates, K is the low-order frequency multiple of the frequency at which the rotor blade passes the stator blade, EO i is the number of the stator blades, max(EO i ) is the maximum number of the stator blades;

[0018] The periodicity of the aerodynamic pressure on the rotor blades satisfies the following conditions:

[0019]

[0020] Among them, P N The aerodynamic pressure on the rotor blades at the last time step, P M is the aerodynamic pressure at the same position of the rotor blade in the previous time step, and ε is a preset value.

[0021] In some specific embodiments, the acquisition of the potential resonance point satisfies the following conditions:

[0022] The position where the natural frequency of the rotor blade is the same as the excitation frequency of the excitation identification result of the rotor blade is the potential resonance point;

[0023] The natural frequency of the rotor blades satisfies the following conditions:

[0024] f m =(kN BL ±m)Ω

[0025] Among them, f m is the natural frequency of the rotor blade with a pitch diameter of m, m is the pitch diameter of the rotor blade, N BL is the number of the rotor blades, Ω is the rotational speed of the rotor blades, and k=0, 1, 2,…

[0026] In some specific embodiments, obtaining the detuning parameters of multiple groups of blade disks of the same specification based on the natural frequency of the potential resonance point includes the following steps:

[0027] determining the number of the rotor blades to be used as a sample;

[0028] measuring the natural frequency at each of the potential resonance points of each of the rotor blades as a specimen;

[0029] Based on the natural frequency of the rotor blade, obtaining a mean and a standard deviation of the natural frequency of the blade disk;

[0030] Based on the mean and standard deviation of the blade disk, a plurality of groups of detuning parameters of the blade disk are obtained.

[0031] In some specific embodiments, the mean of the natural frequencies of the blade disk is an unbiased estimate of the mean of the natural frequencies of the rotor blades as a sample;

[0032] When the number of the rotor blades used as a sample is less than 20, the standard deviation of the natural frequency of the blade disk is determined by the following formula:

[0033]

[0034] Wherein, s is the standard deviation of the natural frequency of the blade disk, σ is the standard deviation of the natural frequency of each of the rotor blades used as a sample, and n is the number of the rotor blades used as a sample;

[0035]

[0036] In some specific embodiments, obtaining the detuning parameters of multiple groups of the blade disks based on the mean and standard deviation of the blade disks comprises the following steps:

[0037] According to the mean and standard deviation of the natural frequency of the blade disk, it can be obtained that the natural frequency of the blade disk obeys the normal distribution of the mean and standard deviation;

[0038] According to the normal distribution of the natural frequencies of the blade disks obeying the mean and standard deviation, multiple groups of natural frequencies of the blade disks can be obtained;

[0039] According to the natural frequencies of the plurality of blade disks, the detuning parameters of the plurality of blade disks can be obtained.

[0040] In some specific embodiments, the detuning parameter of the blade disk is determined by the following formula:

[0041]

[0042] Among them, δ j is the detuning parameter of the blade disk, is the mean value of the natural frequency of the blade disk, f j is the natural frequency of the blade disk obtained according to the mean of the natural frequency of the blade disk.

[0043] In some specific embodiments, obtaining the uncertainty high cycle fatigue evaluation result of the blade disk based on the deharmonic vibration amplitude includes the following steps:

[0044] repeatedly calculating the detuning parameter of the blade disk;

[0045] Obtaining a detuned vibration amplitude of the blade disk according to a plurality of detuned parameters of the blade disk;

[0046] Obtaining the blade disk amplitude amplification factor according to the deresonant vibration amplitude;

[0047] determining the vibration stress of the blade disk according to the amplitude amplification factor;

[0048] The uncertain high cycle fatigue results of the blade disk are evaluated according to the vibration stress of the blade disk.

[0049] In some specific embodiments, the vibration stress for evaluating the uncertainty high cycle fatigue result of the blade disk is determined by the following formula:

[0050]

[0051] Among them, S mist is the vibration stress of the blade disk after detuning, S0 is the vibration stress of the blade disk when it is coordinated, is the mean value of the amplitude magnification factor, F σ is the standard deviation of the amplitude magnification factor

[0052] A system based on the same concept for evaluating uncertain high-cycle fatigue of detuned blade disks includes:

[0053] A model unit for determining and simulating a blade disk model including rotor blades and stator blades;

[0054] an excitation identification unit, configured to obtain an excitation identification result of the rotor blade based on the blade disk model run in simulation;

[0055] a frequency identification unit, configured to obtain a potential resonance point on the rotor blade based on the excitation identification result, and measure a natural frequency of the potential resonance point;

[0056] a detuning parameter algorithm unit, configured to obtain detuning parameters of a plurality of groups of blade disks of the same specification based on the natural frequency of the potential resonance point;

[0057] an amplitude algorithm unit, configured to obtain, based on a plurality of groups of detuning parameters, a detuning vibration amplitude of the blade disk corresponding to the detuning parameters;

[0058] A judgment unit is used to obtain an evaluation result of uncertain high-cycle fatigue of the blade disk based on the deharmonic vibration amplitude.

[0059] The method for assessing uncertain high-cycle fatigue of a detuned blade disk, presented in this paper, measures the natural frequency of a potential resonance point of a rotor blade on a blade disk model to obtain multiple sets of blade disk detuning parameters. This improves the efficiency of detuning parameter measurement and reduces workload. It also avoids the need for artificially limiting detuning parameters, improving the accuracy of test measurement results. Furthermore, the detuning vibration amplitude of the blade disk can be determined from these multiple sets of detuning parameters, enhancing the robustness of the high-cycle fatigue assessment results.

[0060] The system for evaluating uncertain high cycle fatigue of a detuned blade disk of the present invention has the same beneficial effects as the above-mentioned method for determining high cycle fatigue of a detuned blade disk, and will not be described in detail here.

[0061] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0063] Figure 1 A flow chart of a method for determining high cycle fatigue of a detuned blade disk in an embodiment of the present invention is shown;

[0064] Figure 2 A schematic diagram showing the results of the amplitude amplification factor of the blade disk in an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0065] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0066] like Figure 1 As shown, the present invention provides a method for evaluating uncertainty high cycle fatigue of a detuned blade disk, comprising the following steps:

[0067] Determine and simulate a bladed disk model consisting of rotor blades and stator blades;

[0068] Specifically, the blade disk model must contain at least one rotor blade and the front and rear stator blades to meet the basic requirements of model simulation;

[0069] Based on the blade disk model of the simulation run, the excitation identification results of the rotor blades are obtained;

[0070] Specifically, the excitation identification results of the rotor blade include the excitation frequency and amplitude of each node on the rotor blade. Through CFD simulation analysis, the surface of the rotor blade used as a sample can be discretized, so that a grid and nodes exist on the surface of the rotor blade used as a sample. Each node has pressure data. The pressure data is the interference of the aerodynamic pressure when the rotor blade rotates, which is the excitation. The frequency of the excitation received by each node on the surface of the rotor blade needs to be determined, which is the excitation frequency. The number of nodes needs to be determined according to the actual situation. The number of nodes required for rotor blades of different specifications is also different.

[0071] Furthermore, the fast Fourier transform method can be used to perform spectral analysis on the pressure data of each node on the rotor blade and identify the main excitation, where the main excitation is the larger interference encountered by the rotor blade when it rotates, while the smaller interference encountered by the rotor blade when it rotates can be ignored, thereby reducing a certain amount of workload while ensuring the test effect.

[0072] Based on the excitation identification results, the potential resonance points on the rotor blades are obtained and the natural frequencies of the potential resonance points are determined;

[0073] Specifically, it is necessary to calculate and determine the natural frequency of the rotor blade. When the natural frequency of the rotor blade is equal to the excitation frequency, and the natural frequency of the rotor blade meets the requirements with the number of pitch diameters, resonance will occur at the node, and this node is the potential resonance point.

[0074] The acquisition of potential resonance points requires the following conditions to be met, that is, the natural frequency of the rotor blades meets the following conditions:

[0075] f m =(kN BL ±m)Ω

[0076] Among them, f m is the natural frequency of the rotor blade with a pitch diameter of m, m is the pitch diameter of the rotor blade, N BL is the number of rotor blades, Ω is the rotational speed of the rotor blades, k=0,1,2,…

[0077] Furthermore, the blade disk model is simulated to obtain the excitation identification results of the rotor blades and the natural frequency of the potential resonance point. Before this step, the following steps need to be set:

[0078] When simulating the blade disk model, in order to meet the sampling requirements for subsequent spectrum analysis to identify excitation, it is necessary to control the weekly time step of the rotor blade rotation so that the weekly time step meets the sampling frequency requirements;

[0079] The weekly time step refers to the number of calculations required for each rotation of the rotor blade. The calculation of each time step can obtain the pressure data on a rotor blade, that is, one sampling is performed.

[0080] The weekly time step during the rotation of the rotor blades needs to satisfy the following conditions:

[0081] N s >2K·max(EO i )

[0082] Among them, N s is the time step per week when the rotor blade rotates, K is the low-order frequency multiple of the frequency when the rotor blade passes the stator blade, EOi is the number of stator blades, max(EO i ) is the maximum number of stator blades; when the above conditions are met, it means that the required excitation frequency can be obtained and possible aliasing phenomena can be avoided.

[0083] The aerodynamic pressure on the rotor blades is extracted and determined, so that the pressure data of each node on the rotor blades can be obtained. At the same time, it is necessary to control the continuous operation of the rotor blades so that the periodicity of the aerodynamic pressure on the rotor blades meets the requirements.

[0084] Furthermore, K is a low-order multiple of the frequency at which the rotor blade passes the stator blade. The value of K is preferably greater than or equal to 2, so as to obtain a sufficiently high sampling frequency.

[0085] The periodicity of the aerodynamic pressure on the rotor blades requires the following conditions to be met:

[0086]

[0087] Among them, P N is the aerodynamic pressure on the rotor blades at the last time step, P M is the aerodynamic pressure at the same position of the rotor blade in the previous time step, and ε is a preset value. When the aerodynamic pressure on the rotor blade is periodic, starting the subsequent excitation recognition operation can improve the accuracy of the recognition results.

[0088] Based on the natural frequencies of potential resonance points, the detuning parameters of multiple blade disks are obtained;

[0089] Specifically, based on the natural frequency of the potential resonance point, obtaining the detuning parameters of multiple sets of blade disks includes the following steps:

[0090] The number of rotor blades to be used as samples is determined in advance to prepare for subsequent operations; and the natural frequency at each potential resonance point of each rotor blade to be used as a sample is measured respectively. The potential resonance point of each rotor blade to be used as a sample and the natural frequency at each potential resonance point can be determined in the above manner.

[0091] Furthermore, the excitation received by one of the rotor blades may be calculated preferentially, and the excitation received by the other rotor blades may be obtained by converting the excitation amplitude received by the rotor blade obtained by calculation and the phase difference between the other rotor blades.

[0092] The phase difference Δφ between adjacent rotor blades can be determined by the following formula:

[0093]

[0094] Where Δφ is the phase difference, E ois the frequency multiple of the excitation to the rotor blades, N BL is the number of rotor blades. By calculating the excitation received by one rotor blade, the excitation data received by each rotor blade can be obtained, which greatly improves the calculation efficiency.

[0095] By testing the natural frequency of the rotor blade as a sample, the mean and standard deviation of the natural frequencies of other batch-produced blade disks are obtained;

[0096] Specifically, by testing the natural frequency of each potential resonance point of a portion of the rotor blades used as samples, the mean and standard deviation of the natural frequencies of blade disks produced in batches under the same structure and process conditions can be obtained.

[0097] Among them, the mean of the natural frequency of the rotor blade as a sample can be used as an unbiased estimate of the blade disks produced in other batches. The natural frequency of the blade disks produced in other batches can be estimated by measuring the natural frequency of some rotor blades. The mean of the natural frequency of the rotor blade as a sample can be used to represent the mean of the natural frequency of the blade disks produced in other batches, which is an unbiased estimate.

[0098] The natural frequencies of other batch-produced blade disks can be obtained by using fewer rotor blades as samples. When the number of samples is small (e.g., less than 20), the standard deviation of the natural frequencies of other batch-produced blade disks needs to be corrected by the standard deviation of the natural frequencies of the rotor blades used as samples. The standard deviation of the natural frequencies of other batch-produced blade disks is determined by the following formula:

[0099]

[0100] in, s is the standard deviation of the natural frequency of blade disks produced in other batches, σ is the standard deviation of the natural frequency of the rotor blades used as samples, and n is the number of rotor blades used as samples; the test measurement process is reduced and the test measurement efficiency is improved.

[0101] Furthermore, the standard deviation σ of the natural frequency of each rotor blade as a sample is determined by the following formula:

[0102]

[0103] Where σ is the standard deviation of the natural frequency of the rotor blades used as the sample, n is the number of rotor blades used as the sample, is the mean of the natural frequencies of the rotor blades used as the specimen, f i is the test frequency of the rotor blade used as the specimen.

[0104] Based on the mean and standard deviation of the blade disks, the detuning parameters of multiple groups of blade disks are obtained.

[0105] Specifically, obtaining the detuning parameters of multiple groups of blade disks based on the mean and standard deviation of the blade disks includes the following steps:

[0106] According to the mean and standard deviation of the natural frequency of the blade disk, the mean of the natural frequency of the blade disk can be obtained. and a normal distribution with standard deviation s;

[0107] According to the mean of the natural frequency of the blade disk The normal distribution with the standard deviation s can be randomly generated to obtain the natural frequencies of multiple groups of blade disks; by measuring and calculating the frequencies of some rotor blades, the detuning parameters of mass-produced blades can be obtained.

[0108] Specifically, the detuning parameter of the blade disk is determined by the following formula:

[0109]

[0110] Among them, δ j is the detuning parameter of the blade disk, is the mean value of the natural frequency of the blade disk, f j is the natural frequency of the blade disk obtained by obeying the mean of the natural frequency of the blade disk.

[0111] Furthermore, the detuning stiffness of the blade disk can be obtained through the detuning parameter of the blade disk. The detuning stiffness of the blade disk is determined by the following formula:

[0112] [K j ]=(1+δ j )[K0]

[0113] Among them, δ j is the detuning parameter of the blade disk, [K j ] is the detuned stiffness of the blade disk, and [K0] is the stiffness matrix of the blade disk in the tuned state.

[0114] Based on multiple sets of detuning parameters, obtaining detuning vibration amplitudes of the blade disk corresponding to the detuning parameters;

[0115] It should be noted that the method of simply obtaining the detuning vibration amplitude of the blade disk corresponding to the detuning parameters based on multiple sets of detuning parameters is a conventional technique, wherein the multiple sets of detuning parameters serve as input parameters and the detuning vibration amplitude of the blade disk serves as an output parameter.

[0116] Based on the detuned vibration amplitude, the uncertain high-cycle fatigue evaluation results of the randomly detuned blade disk are obtained.

[0117] Specifically, obtaining the uncertainty high-cycle fatigue evaluation results of the randomly detuned blade disk based on the detuned vibration amplitude includes the following steps:

[0118] Repeatedly calculate the detuning parameters of the blade disk; perform batch calculations on the detuning parameters of the blade disk, preferably with the number of calculations greater than or equal to 200 times. And obtain the corresponding detuning vibration amplitude of the blade disk based on all the calculated detuning parameters of the blade disk;

[0119] The amplitude amplification factor of the blade disk is obtained according to the deresonant vibration amplitude; the amplitude amplification factor is determined by the following formula:

[0120]

[0121] Among them, F m is the amplitude amplification factor; the harmonic vibration amplitude is the vibration amplitude when the detuning parameter of the blade disk is equal to 0. Figure 2 As shown, the amplitude amplification factor of the blade disk is clearly represented by a scatter plot and a histogram.

[0122] The mean and standard deviation of the amplitude magnification coefficient of the blade disk can be obtained by the obtained amplitude magnification coefficient of the blade disk. The calculation method of the mean and standard deviation of the amplitude magnification coefficient of the blade disk is the same as the calculation method of the mean and standard deviation of the natural frequency of the blade disk.

[0123] Evaluate the uncertain high-cycle fatigue assessment results of detuned blade disks based on the amplitude magnification factor.

[0124] Specifically, the vibration stress of the blade disk after detuning can be obtained through the amplitude amplification factor of the blade disk, and thus the high cycle fatigue of the blade disk can be evaluated through the obtained vibration stress of the blade disk after detuning.

[0125] The vibration stress used to evaluate the high cycle fatigue of the blade disk is determined by the following formula:

[0126]

[0127] Among them, S mist is the vibration stress after the blade disk is detuned, S0 is the vibration stress when the blade disk is coordinated, is the mean value of the amplitude magnification factor, F σ is the standard deviation of the amplitude amplification factor.

[0128] At the same time, the vibration stress and steady-state stress need to meet the following requirements:

[0129]

[0130] Among them, σ -1 is the minimum fatigue limit of the blade disk, σ bis the strength limit of the blade disk material, and λ is the fatigue reserve coefficient of the blade disk.

[0131] Based on the above-mentioned method for evaluating the uncertainty high cycle fatigue of a detuned blade disk, the present invention further provides a system for evaluating the uncertainty high cycle fatigue of a detuned blade disk, comprising:

[0132] A model unit for determining and simulating a blade disk model including rotor blades and stator blades;

[0133] an excitation identification unit, configured to obtain an excitation identification result of a rotor blade based on a blade disk model run in simulation;

[0134] A frequency identification unit, configured to obtain a potential resonance point on the rotor blade based on the excitation identification result and measure the natural frequency of the potential resonance point;

[0135] A detuning parameter algorithm unit is used to obtain detuning parameters of multiple groups of blades of the same specification based on the natural frequency of the potential resonance point;

[0136] An amplitude algorithm unit, configured to obtain, based on multiple sets of detuning parameters, detuning vibration amplitudes of the blade disk corresponding to the detuning parameters;

[0137] The judgment unit is used to obtain an uncertain high-cycle fatigue assessment result of the mass-produced detuned blade disk based on the detuned vibration amplitude.

[0138] Test results:

[0139] Four sets of calculations were performed, each with 500 random detunings, for a total of 2000 random detunings.

[0140] Table 1. Robustness analysis results of the amplitude amplification factor of the maximum vibration amplitude of the blade disk

[0141] Grouping mean Coefficient of variation Mean difference (%) Coefficient of variation difference (%) Group 1 (1-500) 1.638 0.0734 0.18 3.23 Group 2 (500-1000) 1.64 0.0712 0.31 0.14 Group 3 (1000-1500) 1.633 0.0683 -0.12 -3.94 Group 4 (1500-2000) 1.63 0.0714 -0.31 0.42 Average (1-2000) 1.635 0.0711 — —

[0142] Table 2. Dispersion verification results of the amplitude amplification factor of the blade disk

[0143] frequency Coefficient of variation of all leaves Cv Test value 0.3227 Calculated value 0.37 error 15％

[0144] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for evaluating uncertainty high cycle fatigue of a detuned blade disk, characterized in that: The following steps are involved: Determine and simulate a bladed disk model consisting of rotor blades and stator blades; obtaining an excitation identification result of the rotor blade based on the blade disk model of the simulation operation; Based on the excitation identification result, obtaining a potential resonance point on the rotor blade, and determining a natural frequency of the potential resonance point; Based on the natural frequency of the potential resonance point, detuning parameters of multiple groups of blade disks of the same specification are obtained, which includes the following steps: determining the number of the rotor blades used as samples; measuring the natural frequency at each potential resonance point of each rotor blade used as a sample; based on the natural frequency of the rotor blade, obtaining the mean and standard deviation of the natural frequency of the blade disk; based on the mean and standard deviation of the blade disk, obtaining detuning parameters of multiple groups of blade disks; Based on the multiple groups of detuning parameters, obtaining the detuning vibration amplitude of the blade disk corresponding to the detuning parameters; An uncertain high cycle fatigue evaluation result of the blade disk is obtained based on the deharmonic vibration amplitude.

2. The method for evaluating uncertainty high cycle fatigue of a detuned blade disk according to claim 1, characterized in that: Before obtaining the excitation identification result of the rotor blade based on the blade disk model running the simulation and determining the natural frequency of the potential resonance point, the following steps are provided: Simulating and running the blade disk model to control the weekly time step of the rotor blades to meet the sampling frequency requirement; The aerodynamic pressure on the rotor blades is extracted and determined, and the aerodynamic pressure on the rotor blades is controlled to periodically meet requirements.

3. The method for evaluating uncertain high cycle fatigue of a detuned blade disk according to claim 2, characterized in that: The rotor blades rotate in a weekly time step that satisfies the following conditions: in, is the time step per week when the rotor blade rotates, K is the low-order multiple of the frequency at which the rotor blade passes the stator blade, is the number of the stator blades, is the maximum number of the stator blades; The periodicity of the aerodynamic pressure on the rotor blades satisfies the following conditions: in, The aerodynamic pressure on the rotor blades for the last one-week time step, is the aerodynamic pressure at the same position of the rotor blade in the previous time step, is the preset value.

4. The method for evaluating uncertain high cycle fatigue of a detuned blade disk according to claim 1, characterized in that: The acquisition of the potential resonance point satisfies the following conditions: The position where the natural frequency of the rotor blade is the same as the excitation frequency of the excitation identification result of the rotor blade is the potential resonance point; The natural frequency of the rotor blades satisfies the following conditions: in, is the natural frequency of the rotor blade with a pitch diameter of m, m is the pitch diameter of the rotor blade, is the number of the rotor blades, is the rotational speed of the rotor blades, .

5. The method for evaluating uncertain high cycle fatigue of a detuned blade disk according to claim 1, characterized in that: The mean of the natural frequencies of the blade disk is an unbiased estimate of the mean of the natural frequencies of the rotor blades as a sample; When the number of the rotor blades used as a sample is less than 20, the standard deviation of the natural frequency of the blade disk is determined by the following formula: in, is the standard deviation of the natural frequency of the blade disk, is the standard deviation of the natural frequency of each of the rotor blades as a specimen, is the number of the rotor blades used as a sample; .

6. The method for evaluating uncertain high cycle fatigue of a detuned blade disk according to claim 1, characterized in that: The step of obtaining the detuning parameters of the plurality of blade disks based on the mean and standard deviation of the blade disks comprises the following steps: According to the mean and standard deviation of the natural frequency of the blade disk, it can be obtained that the natural frequency of the blade disk obeys the normal distribution of the mean and standard deviation; According to the normal distribution of the natural frequencies of the blade disks obeying the mean and standard deviation, multiple groups of natural frequencies of the blade disks can be obtained; According to the natural frequencies of the plurality of blade disks, the detuning parameters of the plurality of blade disks can be obtained.

7. The method for evaluating uncertain high cycle fatigue of a detuned blade disk according to claim 6, characterized in that: The detuning parameter of the blade disk is determined by the following formula: in, is the detuning parameter of the blade disk, is the mean value of the natural frequency of the blade disk, is the natural frequency of the blade disk obtained according to the mean of the natural frequency of the blade disk.

8. The method for evaluating uncertainty high cycle fatigue of a detuned blade disk according to any one of claims 1 to 7, characterized in that: The step of obtaining the uncertainty high cycle fatigue evaluation result of the blade disk based on the deharmonic vibration amplitude comprises the following steps: repeatedly calculating the detuning parameter of the blade disk; Obtaining a detuned vibration amplitude of the blade disk according to a plurality of detuned parameters of the blade disk; Obtaining the blade disk amplitude amplification factor according to the deresonant vibration amplitude; determining the vibration stress of the blade disk according to the amplitude amplification factor; The uncertain high cycle fatigue results of the blade disk are evaluated according to the vibration stress of the blade disk.

9. The method for evaluating uncertain high cycle fatigue of a detuned blade disk according to claim 8, characterized in that: The vibration stress for evaluating the uncertainty of the high cycle fatigue results of the blade disk is determined by the following formula: in, is the vibration stress of the blade disk after detuning, is the vibration stress of the blade disk during coordination, is the mean value of the amplitude amplification factor, is the standard deviation of the amplitude amplification factor.

10. A system for evaluating uncertainty high cycle fatigue of a detuned blade disk, characterized in that: include: A model unit for determining and simulating a blade disk model including rotor blades and stator blades; an excitation identification unit, configured to obtain an excitation identification result of the rotor blade based on the blade disk model run in simulation; a frequency identification unit, configured to obtain a potential resonance point on the rotor blade based on the excitation identification result, and measure a natural frequency of the potential resonance point; a detuning parameter algorithm unit, configured to obtain detuning parameters of multiple groups of blade disks of the same specification based on the natural frequencies of the potential resonance points, comprising: determining the number of the rotor blades used as samples; measuring the natural frequency of each of the potential resonance points of each of the rotor blades used as samples; obtaining a mean and a standard deviation of the natural frequencies of the blade disks based on the natural frequencies of the rotor blades; and obtaining detuning parameters of multiple groups of blade disks based on the mean and the standard deviation of the blade disks; an amplitude algorithm unit, configured to obtain, based on a plurality of groups of detuning parameters, a detuning vibration amplitude of the blade disk corresponding to the detuning parameters; A judgment unit is used to obtain an evaluation result of uncertain high-cycle fatigue of the blade disk based on the deharmonic vibration amplitude.

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