Method and system for predicting fatigue life of part and readable storage medium

Abstract

The invention relates to a method and a system for predicting the fatigue life of a part and a readable storage medium. The method comprises the following steps: firstly, obtaining an initial strength analysis result of a finite element model of the part and simulation stress data about a hot spot; determining a correlation coefficient in combination with the test stress data and the simulation stress data; correcting the initial strength analysis result by using the correlation coefficient to obtain a corrected strength analysis result; performing fatigue analysis on the finite element model of the part according to the corrected strength analysis result to obtain fatigue life; according to the steps, a finite element strength analysis result required by fatigue analysis is subjected to test correction, the precision of a fatigue analysis input model is improved, namely, all node stress values of the strength analysis result are corrected, and compared with a general pure simulation analysis method, the method has the advantages of high simulation precision and low finite element modeling sensitivity, and is suitable for large-scale popularization and application. And the corrected model can be used for repeated fatigue life simulation analysis caused by the change of the design load in the later period, so that the development period is remarkably shortened.

Description

Technical Field

[0001] The present application relates to the field of automotive computer-aided engineering technology, and in particular to a method, system and readable storage medium for predicting component fatigue life. Background Art

[0002] At present, CAE (Computer Aided Engineering) technology is usually used in the automobile design stage to perform fatigue durability simulation analysis on parts, and the design is guided by judging whether the design meets the requirements based on the simulation results.

[0003] After the design of the parts is completed, samples need to be made for a series of test verifications. The general route is to first conduct the parts durability test verification, and after the parts verification is passed, it will enter the system durability test phase, and after the system verification is passed, it will finally enter the vehicle durability test verification. Therefore, the parts durability test verification is a very critical verification stage. Correspondingly, virtual verification is also carried out in the above order from parts to systems, and then to the whole vehicle.

[0004] The durability test verification of components is completed on the test bench, and the loading load is generally a regular sinusoidal signal, so most of the component fatigue is uniaxial fatigue. The directions of the three principal stresses of uniaxial fatigue do not change with time, but the stress magnitude will change with the sinusoidal loading signal.

[0005] The test cycle of component bench durability test is long, especially the failure type test. In order to find out the durability performance of components, the test will last for two weeks or even longer, resulting in huge test resource occupation and investment in manpower and material resources. Summary of the invention

[0006] The embodiments of the present application provide a method, system and readable storage medium for predicting the fatigue life of components, so as to solve the problem of component bench durability testing in related technologies, especially the problem of long failure type test cycle resulting in the occupation of test resources and investment of manpower and material resources.

[0007] In a first aspect, a method for predicting fatigue life of a component is provided, comprising:

[0008] Obtain the initial strength analysis results of the finite element model of the component, and analyze and obtain the simulated stress data about the hot spots;

[0009] Acquire test stress data of components about hot spots, and determine correlation coefficients in combination with the simulation stress data;

[0010] Using the correlation coefficient to correct the initial strength analysis result to obtain a corrected strength analysis result;

[0011] A fatigue analysis is performed on the finite element model of the component according to the modified strength analysis result to obtain the fatigue life.

[0012] In some embodiments, obtaining the initial strength analysis result of the finite element model of the component includes the following steps:

[0013] Establish a finite element model of the component based on its dimensional data, then set constraints and perform strength simulation analysis under the design load to obtain the node stress information of all nodes of the finite element model of the component;

[0014] The initial strength analysis results are obtained based on the nodal stress information of all nodes.

[0015] In some embodiments, obtaining simulated stress data about hot spots by analyzing the initial strength analysis results includes the following steps:

[0016] Obtaining the position, stress value and stress direction of each node according to the node stress information;

[0017] The node with the largest first principal stress or the target node is regarded as the hot spot;

[0018] The position, stress value and principal stress direction of the hot spot are used to form simulated stress data about the hot spot.

[0019] In some embodiments, performing fatigue analysis on the component finite element model according to the modified strength analysis result comprises the following steps:

[0020] The dynamic stress response data of the finite element model of the component is obtained by using the quasi-static superposition method based on the first principal stress of all nodes in the modified strength analysis results;

[0021] The fatigue life of each node of the finite element model of the component is calculated using the EN fatigue analysis method based on the dynamic stress response data of each node of the finite element model of the component.

[0022] In some embodiments, the test stress data is obtained by applying a design load to the component on a test bench and measuring the stress data using a strain gauge attached to the mounting position of the component.

[0023] In some embodiments, when the hot spot position of the finite element model of the component corresponds to the node position of the component and meets the requirements for pasting the strain gauge, the node position is the installation position;

[0024] When the hot spot position of the finite element model of the component does not meet the requirements for pasting strain gauges at the node position of the component, the first point and the second point of the node position on both sides of the principal stress direction of the hot spot are used as installation positions; the first point has a first design distance from the node position, and the second point has a second design distance from the node position.

[0025] In some embodiments, the test stress data is combined with the simulation stress data to determine the correlation coefficient, comprising the following steps:

[0026] When the hot spot position of the finite element model of the component corresponds to the node position of the component and meets the requirements for pasting strain gauges, the following formula 1 is used for calculation:

[0027]

[0028] Among them, η is the correlation coefficient, σ h实 is the stress value at the installation position, σ h仿 is the stress value of the hot spot;

[0029] When the hot spot position of the finite element model of the component does not meet the requirements for pasting strain gauges at the node position of the component, the stress values ​​of the first point and the second point in the finite element model of the component and the stress values ​​measured by the strain gauges at the first point and the second point are obtained, and then calculated according to the following formula 2:

[0030]

[0031] Among them, η is the correlation coefficient, σ a实 is the stress value measured by the strain gauge corresponding to the first point, σ a仿 is the stress value corresponding to the first point in the finite element model of the component, σ b实 is the stress value measured by the strain gauge at the second point, σ b仿 is the stress value corresponding to the second point in the finite element model of the component, L a is the first design distance, L b is the second design distance.

[0032] In some embodiments, the initial strength analysis result is corrected using the correlation coefficient to obtain a corrected strength analysis result, comprising the following steps:

[0033] The stress values ​​of all nodes in the initial strength analysis result are multiplied by the correlation coefficient to obtain a modified strength analysis result.

[0034] In a second aspect, a system for predicting component fatigue life is provided, the system for predicting component fatigue life comprising:

[0035] The first module is used to obtain the initial strength analysis results of the finite element model of the component and analyze and obtain the simulation stress data about the hot spot;

[0036] The second module is used to obtain the test stress data of the component about the hot spot and determine the correlation coefficient in combination with the simulation stress data;

[0037] A third module is used to modify the initial strength analysis result using the correlation coefficient to obtain a modified strength analysis result;

[0038] The fourth module is used to perform fatigue analysis on the finite element model of the component according to the modified strength analysis result to obtain fatigue life.

[0039] In a fourth aspect, a computer-readable storage medium is provided, on which a program for predicting component fatigue life is stored, wherein when the program for predicting component fatigue life is executed by a processor, the steps of a method for predicting component fatigue life are implemented.

[0040] The beneficial effects of the technical solution provided by this application include:

[0041] The embodiments of the present application provide a method, system and readable storage medium for predicting the fatigue life of components, which first obtains the initial strength analysis results of the finite element model of the component and the simulation stress data about the hot spots; then determines the correlation coefficient by combining the experimental stress data and the simulation stress data; then uses the correlation coefficient to correct the initial strength analysis results to obtain the corrected strength analysis results; fatigue analysis is performed on the finite element model of the component according to the corrected strength analysis results to obtain the fatigue life; the above steps experimentally correct the finite element strength analysis results required for fatigue analysis, improve the accuracy of the fatigue analysis input model, that is, correct all node stress values ​​of the strength analysis results, compared with the general pure simulation analysis method, it has the advantages of high simulation accuracy and low sensitivity to finite element modeling, and the corrected model can be used for repeated fatigue life simulation analysis caused by later design load changes, significantly shortening the development cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0043] Figure 1 A cloud diagram showing the distribution of the first principal stress magnitudes of all nodes of the control arm model provided in the embodiment of the present application;

[0044] Figure 2 A cloud diagram showing the distribution direction of the first principal stress of all nodes of the control arm model provided in the embodiment of the present application;

[0045] Figure 3 A distribution cloud diagram of the hot spot position, stress magnitude, and first principal stress direction of the control arm model provided in an embodiment of the present application;

[0046] Figure 4 A diagram of a test data acquisition scheme for facilitating the attachment of strain gauges provided in an embodiment of the present application;

[0047] Figure 5 A diagram of a test data acquisition scheme for an embodiment of the present application in which it is inconvenient to attach a strain gauge;

[0048] Figure 6 A schematic diagram of a general process of a method for predicting fatigue life of a component provided in an embodiment of the present application;

[0049] Figure 7 A schematic diagram of a specific process of predicting component fatigue life provided in an embodiment of the present application. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0051] The embodiments of the present application provide a method, system and readable storage medium for predicting the fatigue life of components, so as to solve the problem of component bench durability testing in related technologies, especially the problem of long failure type test cycle resulting in the occupation of test resources and investment of manpower and material resources.

[0052] First, see Figure 6 and Figure 7 , a method for predicting fatigue life of components, comprising:

[0053] Step 100: Obtain the initial strength analysis results of the finite element model of the component, and analyze to obtain the simulation stress data about the hot spot;

[0054] Step 101, obtaining the test stress data of the component about the hot spot, and determining the correlation coefficient in combination with the simulation stress data;

[0055] Step 102: using the correlation coefficient to correct the initial strength analysis result to obtain a corrected strength analysis result;

[0056] Step 103: Perform fatigue analysis on the finite element model of the component according to the modified strength analysis result to obtain fatigue life.

[0057] First, the initial strength analysis results of the finite element model of the component and the simulation stress data about the hot spot are obtained; then the correlation coefficient is determined by combining the test stress data and the simulation stress data; then the initial strength analysis results are corrected using the correlation coefficient to obtain the corrected strength analysis results; fatigue analysis is performed on the finite element model of the component according to the corrected strength analysis results to obtain the fatigue life; the above steps experimentally correct the finite element strength analysis results required for fatigue analysis, and improve the accuracy of the fatigue analysis input model. Based on the correlation coefficient, all node stress values ​​of the strength analysis results are corrected, and finally, based on the corrected strength analysis results, the first principal stress method + quasi-static superposition method + EN fatigue method are used to perform bench life analysis on the component.

[0058] Compared with general pure simulation analysis methods, it has the advantages of high simulation accuracy and low sensitivity to finite element modeling. The corrected model can be used for repeated fatigue life simulation analysis caused by later design load changes (the principal stress direction has not changed and it still belongs to the uniaxial fatigue category), which significantly shortens the development cycle.

[0059] In some preferred embodiments, how to obtain the simulated stress data about the hotspot is described in detail:

[0060] Step 10001, obtaining the initial strength analysis result of the finite element model of the component, including the following steps:

[0061] Establish a finite element model of the component based on its dimensional data, then set constraints and perform strength simulation analysis under the design load to obtain the node stress information of all nodes of the finite element model of the component;

[0062] The initial strength analysis results are obtained based on the nodal stress information of all nodes.

[0063] Step 10002: Analyze the initial strength analysis results to obtain simulation stress data about the hotspot, including the following steps:

[0064] According to the node stress information, the position, stress value and stress direction of each node are obtained;

[0065] The node or target node with the largest first principal stress is regarded as the hot spot; the target node is the location node of the component that is of great concern, such as the part that is subjected to large force or is easily damaged during use; the first principal stress should be understood as follows: the first principal stress is the largest principal stress in a unit. When there is only normal stress and no shear stress on a certain inclined plane, this inclined plane is called the principal plane, the corresponding normal stress is called the principal stress, and the corresponding direction is called the principal direction. The first principal stress is the largest of the three principal stresses, also known as the maximum principal stress. In the stress state, the first principal stress is the most important parameter. It determines the maximum bearing capacity of the structure in a specific direction. When designing and analyzing structures, the first principal stress is usually used as a design indicator because it is directly related to the strength and stability of the structure.

[0066] The location of the hot spot, the stress value and the principal stress direction are used to form the simulation stress data about the hot spot.

[0067] The node positions that are directly related to the strength and stability of the component structure are obtained in the above manner. At the same time, the fatigue risk hotspot positions are found through the early finite element strength simulation. Based on the convenience of collecting stress at this position, the actual test plan for subsequent components can be determined, that is, a single fatigue load is then loaded on the test bench to obtain the test stress of the component as a reference, providing a basis for later fatigue prediction.

[0068] In some preferred embodiments, step 101, obtaining the test stress data of the component about the hot spot and determining the correlation coefficient in combination with the simulation stress data, is described in detail how to obtain the actual test plan of the component according to the hot spot determined in the early stage, and obtain the correlation coefficient, as follows:

[0069] Step 10101, test stress data is obtained by applying a design load to the component on the test bench and measuring the strain gauge pasted on the installation position of the component; in addition, considering that it is not convenient to paste the strain gauge at the hot spot position of some parts, the following steps 10102 and 10103 are also set;

[0070] Step 10102: When the hot spot position of the finite element model of the component corresponds to the node position of the component and meets the requirements for pasting the strain gauge, the node position is the installation position;

[0071] When the hot spot position of the finite element model of the component does not meet the requirements for pasting strain gauges at the node position of the component, the first point and the second point of the node position on both sides of the principal stress direction of the hot spot are used as installation positions; the first point has a first design distance from the node position, and the second point has a second design distance from the node position.

[0072] Step 10103, combining the test stress data with the simulation stress data to determine the correlation coefficient, including the following steps:

[0073] When the hot spot position of the finite element model of the component corresponds to the node position of the component and meets the requirements for pasting strain gauges, the following formula 1 is used for calculation:

[0074]

[0075] Among them, η is the correlation coefficient, σ h实 is the stress value at the installation position, σ h仿 is the stress value of the hot spot;

[0076] When the hot spot position of the finite element model of the component does not meet the requirements for pasting strain gauges at the node position of the component, the stress values ​​of the first point and the second point in the finite element model of the component and the stress values ​​measured by the strain gauges at the first point and the second point are obtained, and then calculated according to the following formula 2:

[0077]

[0078] Among them, η is the correlation coefficient, σ a实 is the stress value measured by the strain gauge corresponding to the first point, σ a仿 is the stress value corresponding to the first point in the finite element model of the component, σ b实 is the stress value measured by the strain gauge at the second point, σ b仿 is the stress value corresponding to the second point in the finite element model of the component, L a is the first design distance, L b is the second design distance.

[0079] Due to the specific structural limitations of the components, it is difficult to attach strain gauges to the hotspot area to collect strain. Therefore, based on whether the hotspot area is convenient for arranging strain gauges, the above two test collection schemes are given, which can be understood as:

[0080] The hot spots of the finite element model of the component correspond to the node positions of the component to facilitate the attachment of strain gauges:

[0081] If it is convenient to paste the strain gauge, then directly paste the unidirectional strain gauge at the node position. The direction of the unidirectional strain gauge is along the first principal stress direction of the hotspot. The strain at the node position is collected, and then the collected strain signal is converted into a stress signal. The stress signal is the stress signal at the node position obtained by the test.

[0082] The hotspot position of the finite element model of the component corresponds to the node position of the component, which is not convenient for pasting strain gauges:

[0083] If the node position is not convenient for pasting strain gauges, then find a point that is convenient for pasting strain gauges at the position closest to the principal stress direction of the hot spot and record it as point a, find a point that is convenient for pasting strain gauges at the position closest to the opposite direction of the principal stress and record it as point b, then paste strain gauges A and strain gauges B at points a and b respectively, and the direction of the strain gauges is along the principal stress direction of the hot spot. Collect strain signals at points a and b, and then convert the strain signals into stress signals. The stress signals are the stress signals of points a and b collected in the test; in addition, it is necessary to measure the distance from point a to the node position and the distance from point b to the node position.

[0084] In some preferred embodiments, step 102, using the correlation coefficient to correct the initial strength analysis result to obtain a corrected strength analysis result, specifically includes the following steps:

[0085] The stress values ​​of all nodes in the initial strength analysis results are multiplied by the correlation coefficient to obtain the modified strength analysis results.

[0086] Step 103, performing fatigue analysis on the finite element model of the component according to the modified strength analysis result to obtain fatigue life, specifically comprising the following steps:

[0087] The dynamic stress response data of the finite element model of the component is obtained by using the quasi-static superposition method based on the first principal stress of all nodes in the modified strength analysis results; the first principal stress method belongs to the category of uniaxial fatigue analysis and is suitable for unidirectional load loading conditions of the bench;

[0088] The EN fatigue analysis method is used based on the dynamic stress response data of each node of the finite element model of the component to calculate the fatigue life of each node of the finite element model of the component.

[0089] In summary, this method uses the preliminary finite element strength simulation to find the first hot spot of fatigue risk, determines the component test plan based on the convenience of collecting stress at this location, and then loads a single fatigue load on the test bench to obtain the test stress data of the component. The correlation coefficient between simulation and test is determined by combining the test stress data and simulation stress data, and the initial strength analysis results are corrected with the correlation coefficient. Finally, based on the corrected initial strength analysis results, the first principal stress method, quasi-static superposition method, and EN fatigue method are used to predict the life of the entire component. Compared with the general pure simulation analysis method, it has the advantages of high simulation accuracy and low sensitivity to finite element modeling, and the corrected model can be used for repeated fatigue life simulation analysis caused by later design load changes, significantly shortening the development cycle.

[0090] In addition, two correction methods are provided according to the test conditions, namely, a correction method in which the node position is convenient for pasting strain gauges and a correction method in which it is not convenient for pasting strain gauges. One of the correction methods is selected to determine the correlation coefficient η to meet the actual situation.

[0091] Taking the fatigue analysis of the single-axis rig of the control arm as an example, the fatigue life is predicted according to the above steps:

[0092] 1. Taking the single-axis bench fatigue analysis of the control arm as an example, the finite element model of the control arm is first established, and the boundary conditions of the finite element simulation analysis of the control arm are set according to the boundary conditions (constraints and loads) of the bench fatigue test, and then the strength analysis is performed to obtain the stress information of all nodes in the finite element model of the control arm to obtain the initial strength analysis results; these node stress information includes the magnitude and direction of the first principal stress, and this stress information is the basis for the subsequent fatigue prediction. The node stress magnitude information of the control arm model is as follows Figure 1 As shown, the stress direction information of the control arm model node is as follows: Figure 2 shown.

[0093] 2. Determine the hotspot location of the initial strength analysis results; e.g. Figure 3 As shown, according to the stress information of all nodes of the control arm finite element model, select the node with the largest first principal stress or the location node of important concern, mark the point as a hot spot, and record its position, stress magnitude and principal stress direction. Node 37813 is the hot spot of the finite element model, and its first principal stress value = 222MPa. The node position is obtained by referring to the positions of three hard points: 242mm from the front mounting point of the control arm, 97mm from the rear mounting point, and 280mm from the steering knuckle mounting point. The first principal stress direction of the hot spot is roughly parallel to the lower edge of the upper plate of the control arm.

[0094] 3. Collect and obtain the actual hot spot position of the control arm and the test stress data under the unidirectional load loading condition of the test bench;

[0095] like Figure 4 and Figure 5 The two cases shown are where strain gauges are provided on the actual control arm. Figure 4 The mid-node position is the hot spot position, the node position is marked as c, the strain gauge is marked as C, and the principal stress direction is D; Figure 5 The midpoint position is marked as c, the strain gauge at the first point a is marked as A, the strain gauge at the second point b is marked as B, the principal stress direction is D, L a Marked as the first design distance, L b Marked as the second design distance.

[0096] 4. Obtain the correlation coefficient, and then correct the initial strength analysis result to obtain the corrected strength analysis result; based on the corrected strength analysis result, perform fatigue analysis on the entire control arm. The stress used in the fatigue analysis uses the first principal stress of the corrected strength analysis result (the first principal stress method belongs to the category of uniaxial fatigue analysis and is suitable for unidirectional load loading conditions of the bench), and then uses the quasi-static superposition method based on the first principal stress to obtain the dynamic stress response of the entire finite element model, and finally uses the EN fatigue analysis method based on the dynamic stress response of each node of the model to calculate the fatigue life of each node of the model.

[0097] In a second aspect, a system for predicting component fatigue life is provided, and the system for predicting component fatigue life includes:

[0098] The first module is used to obtain the initial strength analysis results of the finite element model of the component and analyze and obtain the simulation stress data about the hot spot;

[0099] The second module is used to obtain the test stress data of the component about the hot spot and determine the correlation coefficient in combination with the simulation stress data;

[0100] The third module is used to correct the initial strength analysis result by using the correlation coefficient to obtain a corrected strength analysis result;

[0101] The fourth module is used to perform fatigue analysis on the finite element model of the component according to the modified strength analysis result to obtain the fatigue life.

[0102] Among them, the functional implementation of each module in the above-mentioned system for predicting the fatigue life of components corresponds to the steps in the above-mentioned embodiment of the method for predicting the fatigue life of components, and its functions and implementation processes will not be repeated here one by one.

[0103] In a third aspect, an embodiment of the present application provides a device for predicting the fatigue life of components. The device for predicting the fatigue life of components may be a personal computer (PC), a laptop computer, a server, or other device with data processing capabilities.

[0104] In an embodiment of the present application, a device for predicting component fatigue life may include a processor, a memory, a communication interface, and a communication bus.

[0105] The communication bus may be of any type and is used to interconnect the processor, the memory, and the communication interface.

[0106] The communication interface includes input / output (I / O) interface, physical interface and logical interface, etc., which are used to realize the interconnection of devices inside the component fatigue life prediction device, and the interface used to realize the interconnection between the component fatigue life prediction device and other devices (such as other computing devices or user devices). The physical interface can be an Ethernet interface, a fiber optic interface, an ATM interface, etc.; the user device can be a display, a keyboard, etc.

[0107] The memory can be various types of storage media, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), flash memory, optical storage, hard disk, programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), etc.

[0108] The processor may be a general-purpose processor, which may call a component fatigue life prediction program stored in a memory and execute the component fatigue life prediction method provided in the embodiment of the present application. For example, the general-purpose processor may be a central processing unit (CPU). The method executed when the component fatigue life prediction program is called may refer to the various embodiments of the component fatigue life prediction method of the present application, which will not be described in detail here.

[0109] In a fourth aspect, an embodiment of the present application also provides a computer-readable storage medium.

[0110] The computer-readable storage medium of the present application stores a program for predicting component fatigue life, wherein when the program for predicting component fatigue life is executed by a processor, the steps of the method for predicting component fatigue life as described above are implemented.

[0111] Among them, the method implemented when the component fatigue life prediction program is executed can refer to the various embodiments of the component fatigue life prediction method of this application, and will not be repeated here.

[0112] It should be noted that the serial numbers of the above-mentioned embodiments of the present application are only for description and do not represent the advantages or disadvantages of the embodiments.

[0113] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the system or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise expressly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0114] It should be noted that, in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0115] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A method for predicting fatigue life of a component, characterized in that: It includes: Obtain the initial strength analysis results of the finite element model of the component, and analyze and obtain the simulated stress data about the hot spots; Acquire test stress data of components about hot spots, and determine correlation coefficients in combination with the simulation stress data; Using the correlation coefficient to correct the initial strength analysis result to obtain a corrected strength analysis result; A fatigue analysis is performed on the finite element model of the component according to the modified strength analysis result to obtain the fatigue life.

2. The method for predicting component fatigue life according to claim 1, characterized in that: Obtaining the initial strength analysis results of the component finite element model includes the following steps: Establish a finite element model of the component based on its dimensional data, then set constraints and perform strength simulation analysis under the design load to obtain the node stress information of all nodes of the finite element model of the component; The initial strength analysis results are obtained based on the nodal stress information of all nodes.

3. The method for predicting component fatigue life according to claim 2, characterized in that: The simulation stress data about the hot spot is obtained by using the initial strength analysis results, including the following steps: Obtaining the position, stress value and stress direction of each node according to the node stress information; The node with the largest first principal stress or the target node is regarded as the hot spot; The position, stress value and principal stress direction of the hot spot are used to form simulated stress data about the hot spot.

4. The method for predicting component fatigue life according to claim 3, characterized in that: Performing fatigue analysis on the component finite element model according to the modified strength analysis result includes the following steps: The dynamic stress response data of the finite element model of the component is obtained by using the quasi-static superposition method based on the first principal stress of all nodes in the modified strength analysis results; The fatigue life of each node of the finite element model of the component is calculated using the EN fatigue analysis method based on the dynamic stress response data of each node of the finite element model of the component.

5. The method for predicting component fatigue life according to claim 3, characterized in that: The test stress data is obtained by applying a design load to the component on a test bench and measuring the stress data using a strain gauge attached to the mounting position of the component.

6. The method for predicting component fatigue life according to claim 5, characterized in that: When the hot spot position of the finite element model of the component corresponds to the node position of the component and meets the requirements for pasting the strain gauge, the node position is the installation position; When the hot spot position of the finite element model of the component does not meet the requirements for pasting strain gauges at the node position of the component, the first point and the second point of the node position on both sides of the principal stress direction of the hot spot are used as installation positions; the first point has a first design distance from the node position, and the second point has a second design distance from the node position.

7. The method for predicting component fatigue life according to claim 6, characterized in that: The test stress data is combined with the simulation stress data to determine the correlation coefficient, comprising the following steps: When the hot spot position of the finite element model of the component corresponds to the node position of the component and meets the requirements for pasting strain gauges, the following formula 1 is used for calculation: the= s h实 ; s h仿 Among them, η is the correlation coefficient, σ h实 is the stress value at the installation position, σ h仿 is the stress value of the hot spot; When the hot spot position of the finite element model of the component does not meet the requirements for pasting strain gauges at the node position of the component, the stress values ​​of the first point and the second point in the finite element model of the component and the stress values ​​measured by the strain gauges at the first point and the second point are obtained, and then calculated according to the following formula 2: Among them, η is the correlation coefficient, σ a实 is the stress value measured by the strain gauge corresponding to the first point, σ a仿 is the stress value corresponding to the first point in the finite element model of the component, σ b实 is the stress value measured by the strain gauge at the second point, σ b仿 is the stress value corresponding to the second point in the finite element model of the component, L a is the first design distance, L b is the second design distance.

8. The method for predicting component fatigue life according to claim 2, characterized in that: The initial strength analysis result is corrected by using the correlation coefficient to obtain a corrected strength analysis result, comprising the following steps: The stress values ​​of all nodes in the initial strength analysis result are multiplied by the correlation coefficient to obtain a modified strength analysis result.

9. A system for predicting component fatigue life, characterized in that: The component fatigue life prediction system comprises: The first module is used to obtain the initial strength analysis results of the finite element model of the component and analyze and obtain the simulation stress data about the hot spot; The second module is used to obtain the test stress data of the component about the hot spot and determine the correlation coefficient in combination with the simulation stress data; A third module is used to modify the initial strength analysis result using the correlation coefficient to obtain a modified strength analysis result; The fourth module is used to perform fatigue analysis on the finite element model of the component according to the modified strength analysis result to obtain fatigue life.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a component fatigue life prediction program, wherein when the component fatigue life prediction program is executed by a processor, the steps of the component fatigue life prediction method according to any one of claims 1 to 8 are implemented.

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