A method for correcting a bearing tester simulation model

Abstract

The application discloses a kind of bearing tester simulation model correction method, specifically related to bearing dynamics simulation analysis field, based on the rolling bearing dynamics finite element simulation method under the working condition environment of bearing tester, the stress, strain distribution state, vibration response and so on characteristic results of test bearing in the process of running are extracted and the order of magnitude range of analysis result parameter, for the measurement range and precision and model selection of installation strain gauge, sensor and other detection equipment when high-speed heavy-load rolling bearing test test are provided with theoretical basis and effective guidance, and the simulation model is corrected by test detection result, form simulation result to guide test, the mutual comparison of test test correction simulation model reference correction method, to improve rolling bearing simulation detection precision and test level, the method proposed in the application helps to form bearing tester dynamics finite element simulation detection method, to improve the design level and quality of rolling bearing.

Description

Technical Field

[0001] This invention relates to the field of bearing dynamics simulation analysis, and specifically to a method for correcting a bearing testing machine simulation model. Background Technology

[0002] Rolling bearings are crucial components in mechanical transmission, widely used in aerospace, vehicle engineering, and other fields, and are an indispensable core component of transmission systems. Their performance plays a vital role in the stable operation of aero-engines and helicopter main gearboxes. The mechanical relationships between the various components of rolling bearings under operating conditions such as gears and shafts are complex, making dynamic finite element simulation an essential step in the bearing design process.

[0003] Currently, most dynamic studies on rolling bearings focus on simulation analysis of individual bearings, with little attention paid to stress and strain distribution and vibration response analysis under the operating conditions of rolling bearing testing equipment. Previous rolling bearing analyses have largely applied theoretically calculated equivalent loads and equivalent transformed boundary conditions to the inner and outer rings of a single rolling bearing. However, this approach often results in simulation analysis results failing to provide effective theoretical basis and practical guidance for the measurement range, accuracy, and model selection of strain gauges, sensors, and other testing equipment on the testing equipment. This disconnects simulation analysis from experimental testing, hindering the formation of mutually corroborating and comparative methods. Summary of the Invention

[0004] Based on the above background technology, the study of rolling bearing dynamics simulation analysis under bearing testing conditions is of great significance for bearing testing, design and optimization.

[0005] To address the aforementioned problems, this invention presents a method for correcting the simulation model of a bearing testing machine, thereby resolving the issues raised in the background section.

[0006] This invention provides the following technical solution: a method for correcting a simulation model of a bearing testing machine, comprising the following steps:

[0007] S101: Calculate the geometric parameters of the rolling bearing and testing equipment based on the basic parameters of the rolling bearing and testing equipment; create a bearing testing equipment simulation model in SOLIDWORKS software based on the geometric parameters, including the test bearing, the auxiliary bearing, the shaft, the bushing, the bearing support, the radial loader, and the axial loader; characterized in that:

[0008] S102: Mesh the bearing tester simulation model using HyperMesh mesh generation software and export the mesh file in K-file format;

[0009] S103: Import the mesh file into the LS-PrePost software, create an external rigid constraint shell for the solution domain, the external rigid constraint shell includes a bearing housing shell, a radial loader and an axial loader shell, and merge the overlapping nodes of the flexible body and the rigid shell;

[0010] S104: Set up the flexible body SECTION module and rigid body SECTION module on the bearing tester and assign part numbers SECID in sequence. Create the linear elastic material properties of the test bearing, the auxiliary bearing, and the bearing support. Give the rigid body material properties of the shell structure, set the material number MID, and give the degree of freedom constraints according to the working environment. Set the PID of each part in the PART module of the LS-PrePost software, and select SECID and material property MID to make them correspond one-to-one.

[0011] S105: In the LS-PrePost software, the CONTACT module sets the contact of the rolling elements, cage, and inner and outer rings, gives the static friction coefficient and dynamic friction coefficient, and adopts automatic surface-to-surface contact. The contact between the bearing outer ring and the support, the contact between the bearing inner ring and the shaft, and the contact between the bushing and the shaft adopt the surface-to-surface binding contact method.

[0012] S106: Setting boundary conditions, rotational speed, and load for the bearing testing machine simulation model based on high-speed heavy-load operating conditions;

[0013] S107: Define the solution format for the bearing tester simulation model; give the global damping coefficient, solution output format, hourglass control, time step and time step; set the solution memory and CPU cores, submit the calculation and solution in LS-DYNA and export the solution results;

[0014] S108: Based on the calculation results, correct the geometric parameters, mesh generation parameters and boundary conditions of the bearing tester, and repeat S101 to S107 until the actual results are obtained.

[0015] S109: Based on the bearing tester simulation model modified from S108, the simulation stress / strain and velocity / acceleration results are obtained. Based on this, the appropriate strain gauge and sensor models, measurement range and accuracy, and sensitive locations for installing the measuring equipment are selected.

[0016] The present invention has the following advantages:

[0017] Based on the finite element simulation method of rolling bearing dynamics under the operating conditions of a bearing testing machine, this invention extracts and analyzes the stress, strain distribution, vibration response, and other characteristic results of the tested bearing during operation, and provides a theoretical basis and effective guidance for the selection of measurement range, accuracy, and model of testing equipment such as strain gauges and sensors during high-speed heavy-load rolling bearing testing. Furthermore, the invention uses the test results to correct the bearing testing machine simulation model, forming a mutual comparison and correction method where simulation results guide testing, and testing corrects the bearing testing machine simulation model. This improves the accuracy and level of rolling bearing simulation testing. Compared with existing technologies, the method proposed in this invention helps to form a finite element simulation testing method for bearing testing machine dynamics, thereby improving the design level and quality of rolling bearings. Attached Figure Description

[0018] Figure 1 This is a flowchart illustrating the design of a method for correcting the simulation model of a bearing testing machine provided in this embodiment of the invention.

[0019] Figure 2 This is a specific implementation flow of the method for correcting the simulation model of the bearing tester provided in the embodiments of the present invention;

[0020] Figure 3 This is a simulation model of the bearing tester provided in this invention.

[0021] Figure 4 This is the mesh generation result of the bearing tester simulation model provided by the present invention;

[0022] Figure 5 This is a cross-sectional view of the simulation calculation results of the bearing tester according to an embodiment of the present invention;

[0023] Figure 6 This is a graph showing the stress variation over time in a certain unit of the bearing bearing outer ring bearing bearing bearing bearing bearing testing apparatus according to an embodiment of the present invention.

[0024] Figure 7 This is a graph showing the strain variation over time of a certain unit in the bearing bearing outer ring bearing load-bearing area tested by the bearing testing apparatus provided in this invention.

[0025] Figure 8 This is a graph showing the change of Z-axis acceleration over time at a node in the bearing bearing outer ring bearing load area, as provided by an embodiment of the present invention.

[0026] Figure 9 This refers to the selection of the model of the test strain gauge for the bearing tester provided in the embodiments of the present invention;

[0027] Figure 10 This refers to the selection of the test sensor model for the bearing tester provided in the embodiments of the present invention.

[0028] Figure 11 This refers to the selection of the installation position of the test strain gauge / sensor in the bearing tester provided by the present invention. Detailed Implementation

[0029] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] like Figure 1 As shown, this embodiment provides a method for correcting a simulation model of a bearing testing machine, including the following steps:

[0031] S101: Calculate the geometric parameters of the rolling bearing and testing equipment based on their basic parameters; create a bearing testing equipment simulation model in SOLIDWORKS software based on these geometric parameters, including the test bearing, auxiliary bearing, shaft, bushing, bearing support, radial loader, and axial loader, such as... Figure 3-5 As shown;

[0032] Specifically, the geometric parameters of the rollers, cage, inner and outer rings of the three-point contact ball bearing and cylindrical roller bearing are calculated using basic parameters. In SOLIDWORKS software, the rolling elements, cage and inner and outer rings, shaft, radial loader, axial loader and bearing support are created using feature commands such as stretch, rotate and cut. Then, the above parts are assembled and exported in .stp format.

[0033] S102: The simulation model of the bearing tester is meshed using HyperMesh meshing software, and the mesh file is exported in K file format;

[0034] Specifically, the 3D model of the bearing testing equipment in .stp format is imported into HyperMesh for structured mesh generation. In the model module, a new component is created for each part, including the bearing cage, rollers, inner and outer rings, shaft, axial loader, and radial loader, and then moved into a group. The SOI LD edit function is used to symmetrically divide each part, preparing for subsequent mesh generation. For circumferentially symmetrical components such as the axial loader, radial loader, and shaft, one-quarter of the component is cut off, and a 2D mesh with a size of 2mm is generated on its axial surface using the automesh function. After adjusting the settings to form a regular mesh, the 2D mesh is rotated and stretched into a hexahedral mesh with a size of 2mm using SOI LD map. The generated one-quarter component mesh is then mirrored using reflect to obtain the complete mesh model. The same operation is performed to mesh the bearing inner and outer rings, cage, etc., with a size of 1mm. The rolling ball and cylindrical roller adopt a coin-shaped structure. After cutting off one-quarter of the roller, a cube-shaped part is cut out inside. A 2D mesh is generated on the end face using automesh, and then a 3D mesh is extruded outwards with a given size of 1mm. The generated mesh is then mirrored to obtain a complete mesh model. Finally, all generated meshes are merged, with a tolerance of 0.1 selected in the edge function. Nodes inside the parts that exist due to the mirroring operation are merged. After merging, free edges and T-shaped edges are checked in the edge function to ensure the mesh model is correct. The result is then output as a K-file. Figure 4 As shown.

[0035] S103: Import the mesh file into LS-PrePost, create the rigid constraint shell outside the solution domain based on the hexahedral mesh size in S102, including the bearing housing shell, radial loader and axial loader shell, and merge the overlapping nodes of the flexible body and rigid shell;

[0036] Specifically, the process involves importing a K-file mesh model into the LS-PrePost software, selecting ElementGeneration in the MESH module, and generating rigid constraint shells for the bearing housing, radial loader, axial loader, and bearing support housing by selecting solid surfaces, as well as an inner surface rigid constraint shell for applying shaft rotational speed. Then, in ElementTools' Dupl icate Nodes, the duplicate node tolerance is first set to 0.01mm, and then duplicate nodes are displayed and merged to complete the common node setting for flexible and rigid structures such as the bearing housing and its rigid shell, and the radial loader and its rigid shell.

[0037] S104: Set up the SECTION module for flexible bodies and the SECTION module for rigid bodies on the bearing tester and assign SECIDs in sequence. Create the linear elastic material properties of the test bearing (including cylindrical core bearings and three-point contact ball bearings), the test bearing, the bearing support, and other structures. Give the rigid material properties of the shell structure, set the MID, and give the degree of freedom constraints according to the working environment. Set the PID for each part in the PART module, and select the SECID and the material property MID to make them correspond one-to-one.

[0038] Specifically, in the Section module, a SOLID part is created for each component of the flexible structure in the bearing tester, such as the bearing housing, bearing cage, inner and outer rings of the rolling elements, and the force loader. SECIDs are assigned in a specific order, and the element integration formula uses a fully integrated S / R solid format. A SHELL part is created for the bearing housing, radial loader, and axial loader surface rigid constraint shell, with assigned SECIDs, a shear factor of 0.833, and a shell element thickness of 0.8 mm. The element integration formula uses a fully integrated S / R solid format. The material settings for the bearing tester are divided into linear elastic materials and rigid materials. For the linear elastic material settings, the radial loader material density is defined as 7870 kg / m³. 3 The elastic modulus is 2.11 × 10⁻⁶. 11 Pa, Poisson's ratio is 0.277, MID is set to 1, and the density of the inner and outer rings and rollers of the rolling bearing is 7870 kg / m³. 3 The elastic modulus is 2.09 × 10⁻⁶. 11 Pa, Poisson's ratio is 0.3, MID is set to 2, and the cage material density is 7870 kg / m³. 3 The elastic modulus is 2.09 × 10⁻⁶. 11 Pa, Poisson's ratio is 0.295, MID is set to 3, and the given material density for other flexible body parts, including bearing housings, axial loaders, bushings, shafts, etc., is 7700 kg / m³. 3 The elastic modulus is 2.0 × 10⁻⁶. 11 Pa, Poisson's ratio is 0.3, and MID is set to 4. For rigid body material settings, the given material density is 7700 kg / m³. 3 The elastic modulus is 2.0 × 10⁻⁶. 11 Pa, Poisson's ratio is 0.3, and MID is set to 5. All degrees of freedom of the bearing housing are constrained according to the operating conditions, and the Y-direction degree of freedom of the radial loader and the Z-direction degree of freedom of the axial loader are released respectively. Based on the above settings, the corresponding PID, SECID, and MID are assigned to each part in the PART module, while other settings remain at their default values.

[0039] S105: In the CONTACT module, contact settings are configured for the rolling elements, cage, and inner and outer rings. The static friction coefficient and dynamic friction coefficient are given, and the contact method is automatic surface-to-surface contact. The contact between the bearing outer ring and the support, the contact between the bearing inner ring and the shaft, and the contact between the bushing and the shaft are all set to surface-to-surface binding contact.

[0040] Specifically, in the Contact module, the automatic surface-to-surface contact method is used to set the contact between the rollers and the inner and outer rings. The rollers are the driven surface, and both the inner and outer rings are the principal surfaces. The dynamic friction coefficient is 0.15, the static friction coefficient is 0.2, and the exponential decay coefficient is 1×10⁻⁶. -5 The stiffness penalty factor for both the principal and secondary surfaces is given as 1.5; the rolling ball and the inner and outer rings are in contact, with a dynamic friction coefficient of 0.05, a static friction coefficient of 0.1, and an exponential decay coefficient of 1×10⁻⁶. -5 The ball and cage are in contact, with a dynamic friction coefficient of 0.005, a static friction coefficient of 0.01, and an exponential decay coefficient of 1×10⁻⁶. -5 The stiffness penalty factor for both the master and slave surfaces is given as 1.0. The rollers are in slave surface contact, while the inner and outer rings and the cage are in master surface contact. A surface-to-surface contact method is used to set the contact between the bearing outer ring and the bearing housing, and the contact between the inner ring and the shaft. The inner and outer rings are slave surfaces, and the bearing housing and shaft are master surfaces. The dynamic friction coefficient is 0.15, the static friction coefficient is 0.2, and the exponential decay coefficient is 1×10⁻⁶. -5 .

[0041] S106: Setting boundary conditions, rotational speed, and load for bearing testing machine model based on high-speed heavy-load operating conditions.

[0042] Specifically, load and speed curves are defined based on actual working conditions: radial load of 22624.6 N, axial load of 13115.2 N, and speed of 20900 rpm. A ramp loading method is given during the startup phase. In the LOAD module, the rigid housing of the radial load loader is selected as the load application object, with the load direction being the negative Y direction. The rigid housing of the axial load loader is also selected as the load application object, with the load direction being the negative Z direction. In the Boundary module, the rigid shell element on the inner surface of the shaft is selected as the speed application object, and the entire test apparatus rotates around the Z-axis. The axial displacement of the cylindrical roller bearing cage end face node is constrained.

[0043] S107: Define the model solution format; give the global damping coefficient, solution output format, hourglass control, time step and time step; set the solution memory and CPU cores, submit the calculation and solution in LS-DYNA and export the solution results;

[0044] Specifically, in CONTROL, set the solution accuracy, hourglass control, energy control, etc., and set the solution time to 0.05s with a time step of 1×10. -4 In the DAMPING GLOBAL tab, set the global damping factor to 0.05. In the DATABASE FORMAT, set the output format to LS-DYNA database format, output the calculation results in D3PLOT format, and set the time interval between outputs to 1×10. -5 In the Keyword module, set the computation storage to 9999999 and the CPU solver cores to 16. In the ANSYS Mechanical APDL Product Launcher solver module, select LS-DYNA Solver as the simulation environment, correctly select the working directory and K-file import directory, and finally submit the solution.

[0045] S108: Based on the calculation results, correct the geometric parameters, mesh generation parameters and boundary conditions of the bearing tester, and repeat S101 to S107 until the calculated results are consistent with reality.

[0046] Specifically, after completing the solution, the resulting D3PLOT file is imported into LS-PrePost. In POST, parameters such as stress, strain, velocity, and acceleration are output. Based on the simulation results, strain gauges and sensors are installed on the stress-prone parts of the bearing in the bearing testing apparatus. The experimental conclusions are compared with the simulation results to analyze the sources of error. Geometric parameters are corrected, the bearing mesh is refined, and boundary conditions are adjusted. Steps S101 to S107 are repeated until the calculated results match reality. These steps can analyze the influence of load, rotational speed, and cage structure on the roller runout angle within a certain range, and play a crucial role in optimizing the bearing structure and reducing vibration and noise.

[0047] S109: Based on the simulated stress / strain and velocity / acceleration results obtained from the bearing tester simulation model modified in S108, select the strain gauge and sensor models, measurement range and accuracy, and sensitive locations for installing the measuring equipment.

[0048] Specifically, this involves obtaining simulation stress / strain, velocity / acceleration, and other parameter results from the simulation model after correction in step S108, such as... Figure 6-8As shown, the stress magnitude was analyzed to be 200 MPa, and the strain magnitude was within 5 micro-strains. The strain gauge model was selected as BHI350-3AA(11)R12 with a sensitivity coefficient of 1.8–2.20, and the accelerometer model was selected as CT1000G with a transverse sensitivity ratio of less than 3%. The strain gauges and sensors were installed at three locations in the load-bearing area and at the top, where the strain and acceleration were most sensitive during the simulation. Figure 9-11 As shown.

[0049] like Figure 2 As shown, the specific implementation steps are as follows:

[0050] S1: Calculate the geometric parameters of the rolling bearing and the testing equipment based on the basic parameters of the test bearing and the testing equipment;

[0051] S2: Create a bearing tester simulation model in SOLIDWORKS based on the geometric parameters in S1, including the test bearing, the test bearing, the shaft, the bushing, the bearing support, the radial loader, and the axial loader.

[0052] S3: Based on HyperMesh mesh generation software, the bearing tester simulation model is meshed into hexahedral meshes using a structured mesh generation method and the mesh file is exported in K file format;

[0053] S4: Import the mesh file into LS-PrePost and create rigid shell meshes for constraining bearing housings, rigid shell meshes for applying radial and axial forces, and rigid shell elements for adding shaft speeds, based on the hexahedral mesh size in S3.

[0054] S5: Merge the created rigid constraint shells of the bearing housing, radial loader, and axial loader with their corresponding flexible bodies by overlapping nodes;

[0055] S6: Set the SECTION module for flexible bodies and the SECTION module for rigid bodies on the bearing tester and assign them unique SECIDs;

[0056] S7: Create linear elastic material properties for structures such as test bearings, auxiliary bearings, and bearing support seats; give rigid material properties for shell structures; set MIDs and give degree-of-freedom constraints according to the working environment.

[0057] S8: In the PART module, set the PID for each part, and select SECID and material property MID to make them correspond one-to-one;

[0058] S9: Set the contact for the rolling elements, cage, and inner and outer rings, specifying the static and dynamic friction coefficients, and using automatic surface-to-surface contact as the contact method;

[0059] S10: The contact between the outer ring of the bearing and the support, the contact between the inner ring of the bearing and the shaft, and the contact between the bushing and the shaft adopt a surface-to-surface binding contact method;

[0060] S11: Set boundary conditions, speed and load for the bearing tester model based on high-speed heavy-load operating conditions;

[0061] S12: Define the model solution control, including solution accuracy, hourglass control, energy output, and define the time step and solution time;

[0062] S13: Set the output format;

[0063] S14: Given the global damping coefficient,

[0064] S15: Set the solution memory and number of CPU cores;

[0065] S16: Complete the model setup and output in K file format;

[0066] S17: Submit the K file in LS-DYNA for solution calculation;

[0067] S18: Import the solution results into LS-PrePost to extract the results;

[0068] S19: Based on the calculation results of S18, correct the geometric parameters, mesh generation parameters and boundary conditions of the bearing tester, and repeat steps S1 to S18 until the actual results are obtained.

[0069] S20: The simulation stress / strain, velocity / acceleration, and other parameter results obtained from the simulation model after the correction in S19, such as... Figure 6-8 As shown, select the model, measurement range, and accuracy of the strain gauge and sensor, as well as the sensitive location for installing the measuring equipment, such as... Figure 9-11 As shown.

[0070] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A method for correcting a simulation model of a bearing testing machine, comprising the following steps: S101: Calculate the geometric parameters of the rolling bearing and testing equipment based on the basic parameters of the rolling bearing and testing equipment; create a bearing testing equipment simulation model in SOLIDWORKS software based on the geometric parameters, including the test bearing, the auxiliary bearing, the shaft, the bushing, the bearing support, the radial loader, and the axial loader; characterized in that: S102: Mesh the bearing tester simulation model using HyperMesh mesh generation software and export the mesh file in K-file format; S103: Import the mesh file into the LS-PrePost software, create an external rigid constraint shell for the solution domain, the external rigid constraint shell includes a bearing housing shell, a radial loader and an axial loader shell, and merge the overlapping nodes of the flexible body and the rigid shell; S104: Set up the flexible body SECTION module and rigid body SECTION module on the bearing tester and assign part numbers SECID in sequence. Create the linear elastic material properties of the test bearing, the auxiliary bearing, and the bearing support. Give the rigid body material properties of the shell structure, set the material number MID, and give the degree of freedom constraints according to the working environment. Set the PID of each part in the PART module of the LS-PrePost software, and select SECID and material property MID to make them correspond one-to-one. S105: In the LS-PrePost software, the CONTACT module sets the contact of the rolling elements, cage, and inner and outer rings, gives the static friction coefficient and dynamic friction coefficient, and adopts automatic surface-to-surface contact. The contact between the bearing outer ring and the support, the contact between the bearing inner ring and the shaft, and the contact between the bushing and the shaft adopt the surface-to-surface binding contact method. S106: Setting boundary conditions, rotational speed, and load for the bearing testing machine simulation model based on high-speed heavy-load operating conditions; S107: Define the solution format for the bearing tester simulation model; give the global damping coefficient, solution output format, hourglass control, time step and time step; set the solution memory and CPU cores, submit the calculation and solution in LS-DYNA and export the solution results; S108: Based on the calculation results, correct the geometric parameters, mesh generation parameters and boundary conditions of the bearing tester, and repeat S101 to S107 until the actual results are obtained. S109: Based on the bearing tester simulation model modified from S108, the simulation stress / strain and velocity / acceleration results are obtained. Based on this, the appropriate strain gauge and sensor models, measurement range and accuracy, and sensitive locations for installing the measuring equipment are selected.

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