Simulation evaluation method for shoulder carcass delamination damage performance based on minimum principal strain amplitude

Abstract

The present invention relates to the technical field of tire durability performance evaluation, and specifically to a method for simulating and evaluating shoulder carcass delamination damage performance based on minimum principal strain amplitude. The present invention comprises the following steps: S1, establishment of a tire simulation model; S2, simulation calculation of a vertical load condition of the tire; S3, extraction of a shoulder carcass delamination damage index; S4, calculation of the rubber compression strain amplitude near the shoulder carcass; S5, evaluation of shoulder carcass delamination indexes among multiple structural schemes. The present invention is used to evaluate the performance of shoulder carcass delamination damage of a load-bearing radial tire by establishing a tire simulation model, performing simulation calculations under vertical load conditions, extracting a shoulder carcass delamination damage index, calculating the rubber compression strain amplitude, and evaluating the shoulder carcass delamination indexes of different design schemes.

Description

Technical Field

[0001] The invention relates to the technical field of tire durability performance evaluation, and in particular to a simulation evaluation method for shoulder tire delamination damage performance based on minimum principal strain amplitude. Background Art

[0002] In the field of tire design and manufacturing, shoulder carcass delamination of load-carrying radial tires is an important issue that affects tire durability and safety. This problem is particularly prominent in harsh operating environments, such as high air pressure, high load, and complex road conditions. Taking wide-body dump truck tires as an example, the separation between the shoulder carcass and the adjacent shoulder pad rubber layer is one of the main problems that affect the durability of the tire shoulder. Figure 1 As shown. The prior art does not clearly point out the mechanical reasons and evaluation methods for shoulder carcass delamination, and does not provide clear finite element simulation evaluation indicators for this problem. In order to solve the above technical problems, those skilled in the art have made the following efforts. For example, the Chinese patent publication number is CN116502507A, which discloses a simulation evaluation method for the delamination damage performance of a load-bearing radial tire crown. It avoids crown delamination damage too early in the tire use process in the early stage of design through tire loading deformation analysis, and provides effective support for increasing the service life of tire products and improving the research and development efficiency of tire products. However, the shear strain amplitude between the center position of the crown and the outermost belt layer of the above scheme is difficult to obtain, and there is still a lack of another more effective way to realize the simulation evaluation of the shoulder carcass delamination damage performance. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a simulation evaluation method for shoulder carcass delamination damage performance based on minimum principal strain amplitude.

[0004] The technical solution adopted by the present invention is as follows:

[0005] A method for simulating and evaluating shoulder carcass delamination damage performance based on minimum principal strain amplitude includes the following steps:

[0006] S1. Establishment of tire simulation model: discretize the tire design material distribution map into a finite element simulation model;

[0007] S2. Simulation calculation of tire vertical load conditions: through simulation calculation, the three-dimensional geometry, stress and strain results of the tire model under vertical load conditions are obtained;

[0008] S3. Extraction of shoulder carcass delamination damage index: Mechanical analysis shows that the periodic compression of the rubber unit near the shoulder carcass is the mechanical cause of the damage. The minimum principal strain amplitude is used to evaluate the compression strain of the rubber near the shoulder carcass.

[0009] S4. Calculation of the rubber compressive strain amplitude near the shoulder carcass: The minimum principal strain amplitude is defined as the difference between the maximum and minimum minimum principal strains of the rubber unit near the shoulder carcass after one rolling of the tire, which is used to determine that the minimum principal strain amplitude of the rubber unit near the shoulder carcass is an evaluation index for shoulder carcass delamination;

[0010] S5. Evaluation of shoulder carcass delamination index among multiple structural schemes: Simulate and calculate tires of different designs respectively to obtain the minimum principal strain amplitude of the rubber unit near the shoulder carcass, which is the evaluation index of shoulder carcass delamination; the structural scheme with the smallest evaluation index of shoulder carcass delamination is the best scheme.

[0011] This technical solution is used to evaluate the performance of shoulder carcass delamination damage of load-bearing radial tires by establishing a tire simulation model, performing simulation calculations under vertical load conditions, extracting shoulder carcass delamination damage indicators, calculating rubber compression strain amplitude, and evaluating shoulder carcass delamination indicators of different design schemes. Specifically, step S1 discretizes the complex tire structure into a numerical model processed by a computer for subsequent mechanical analysis; step S2 applies a vertical load consistent with the actual working condition to the finite element model, obtains the three-dimensional geometry, stress distribution and strain results of the tire under load through simulation calculation, and simulates the stress conditions of the tire in actual use; step S3 The rubber unit near the shoulder carcass is easily damaged under cyclic compression, and the minimum principal strain amplitude is used as an indicator to evaluate the rubber compression strain near the shoulder carcass. The minimum principal strain amplitude can reflect the fatigue of the material under cyclic loading. The degree of fatigue accumulation; Step S4 defines the minimum principal strain amplitude as the difference between the maximum and minimum values ​​of the minimum principal strain of the rubber unit concerned near the shoulder carcass when the tire rolls one circle. The larger the difference, the more severe the compression deformation of the rubber unit, thereby increasing the risk of delamination damage; Step S5 evaluates the delamination damage risk of each scheme by comparing the simulation calculation results of tires with different design schemes under the same conditions, that is, the minimum principal strain amplitude of the rubber unit near the shoulder carcass, and selects the design scheme with the smallest shoulder carcass delamination evaluation index as the best scheme, because it has a lower delamination risk in theory.

[0012] In addition, the above-mentioned simulation evaluation method for shoulder carcass delamination damage performance based on minimum principal strain amplitude according to the present invention also has the following additional technical features:

[0013] According to one embodiment of the present invention, in S1, establishing the tire simulation model includes the following steps:

[0014] S11. Use 2D drawing software to draw a material distribution map including the inner and outer contours of the tire, the skeleton material, the internal rubber components and the component boundary lines in a 1:1 ratio;

[0015] S12, importing the drawn material distribution map into finite element meshing software, performing finite element meshing on the tire material distribution map, and generating a two-dimensional axisymmetric finite element model;

[0016] S13, define the unit type in the two-dimensional axisymmetric finite element model, wherein the skeleton material unit type is defined as SFMGAX1, and the rubber material unit type is defined as CGAX4H and CGAX3H;

[0017] S14. Referring to the actual working conditions of the tire, the tire simulation model is equipped with a rim and a uniformly distributed pressure consistent with the air pressure is applied, and the finite element analysis software Abaqus is submitted for two-dimensional inflation simulation calculation.

[0018] This technical solution uses the finite element analysis software Abaqus to simulate the actual physical properties and working environment of the tire to predict the performance of the tire under different working conditions. Specifically, step S11 uses two-dimensional drawing software to draw a material distribution map of the tire, which is the basis for establishing a simulation model to ensure that the model can accurately reflect the geometric shape and material composition of the tire, including the inner and outer contours, skeleton materials, internal rubber components and component boundaries; the finite element grid of step S12 is the basic unit of simulation analysis, which discretizes the continuum into a finite number of units, each unit is connected by nodes, and through reasonable grid division, it simulates the complex structure and material properties of the tire while ensuring computational efficiency and accuracy; step S13 defines the unit type in the two-dimensional axisymmetric finite element model, which is selected according to the material properties and mechanical properties of different parts of the tire. The unit type (such as SFMGAX1) of the skeleton material (such as the cord) is usually used to simulate the mechanical behavior of the fiber-reinforced material, while the unit type of the rubber material (such as CGAX4H and CGAX3H) is used to simulate the nonlinearity, viscoelasticity and large deformation characteristics of the rubber material; step S14 refers to the actual working condition of the tire, assembles the rim to the tire simulation model, applies a uniformly distributed pressure consistent with the air pressure, and submits it to the finite element analysis software Abaqus for two-dimensional inflation simulation calculation to simulate the inflation process of the tire in actual use; by applying air pressure and constraints, calculates the geometric shape and internal stress distribution of the tire in the inflated state.

[0019] According to one embodiment of the present invention, in S2, the tire vertical load condition simulation calculation includes the following steps:

[0020] S21, using the SMG technology in the finite element analysis software Abaqus, rotating the two-dimensional finite element mesh obtained in the above S14 to generate a three-dimensional finite element mesh model;

[0021] S22, transferring the two-dimensional finite element inflation analysis result obtained in the above S14 to the three-dimensional finite element mesh model through the SRT technology in the finite element analysis software Abaqus;

[0022] S23. According to the actual load during the use of the tire, a vertical force is applied to the three-dimensional tire model, and the Abaqus standard solver of the finite element analysis software is submitted to perform loading simulation calculations to obtain the three-dimensional loading geometry and three-dimensional stress and strain distribution of the tire simulation model.

[0023] This technical solution uses the SMG and SRT technologies in the Abaqus software, combined with finite element analysis technology, to quickly and accurately construct a three-dimensional tire model, and transfer the two-dimensional inflation analysis results to the three-dimensional model, thereby simulating the stress conditions of the tire under actual working conditions, providing important support for tire performance evaluation and safety analysis. Specifically, step S21 uses the SMG technology in Abaqus to rotate the two-dimensional finite element mesh to generate a three-dimensional finite element mesh model. By rotating the two-dimensional mesh, a three-dimensional tire model is quickly and accurately constructed to provide a basis for subsequent simulation analysis; step S22 uses the SRT technology in Abaqus to transfer the results of the two-dimensional inflation analysis (such as the tire shape and internal stress distribution after inflation) to the three-dimensional model, thereby avoiding the need to repeat the three-dimensional inflation analysis and improving the simulation efficiency; step S23 is a key step in simulating the stress conditions of the tire under actual working conditions. By applying a vertical force consistent with the actual load, the stress conditions of the tire under driving, braking, cornering and other working conditions are simulated. The Abaqus standard solver is a powerful finite element solver that can handle various complex mechanical problems, including nonlinear, large deformation and other problems. By submitting the solver for calculation, the three-dimensional loading geometry and three-dimensional stress and strain distribution of the tire under vertical load conditions are obtained, providing an important basis for evaluating the performance and safety of the tire.

[0024] According to one embodiment of the present invention, in S3, the shoulder carcass delamination damage index extraction includes the following steps:

[0025] S31. In the two-dimensional simulation results, 10 elements of the shoulder pad rubber adjacent to the shoulder carcass and where carcass delamination occurs are selected along the carcass cord direction at the shoulder position, and the position information of the shoulder carcass delamination occurs is included by establishing an element set;

[0026] S32. In the three-dimensional simulation results, extract and record the minimum principal strain amplitude of each unit in the unit set created in step S31 and the three-dimensional generated unit of the unit in the circumferential direction.

[0027] This technical solution uses the results of finite element analysis to select the elements in the key areas and extract their minimum principal strain amplitudes to evaluate the risk of shoulder carcass delamination. Specifically, step S31 locates and analyzes the areas where shoulder carcass delamination is most likely to occur. The shoulder position is one of the places where the tire is subjected to the maximum stress and strain. By selecting 10 elements and establishing an element set, focus on these key areas and extract their mechanical response data; step S32 is used to quantify the risk of shoulder carcass delamination. The minimum principal strain amplitude is an important indicator for evaluating material fatigue and damage accumulation because it reflects the difference between the maximum and minimum strains of the material under cyclic loading. By extracting the minimum principal strain amplitudes of these elements, their strain changes during tire rolling are evaluated and whether they are prone to delamination are predicted. In addition, since the tire is a three-dimensional structure, the elements selected in the two-dimensional simulation results will have multiple corresponding elements in the three-dimensional space (i.e., three-dimensional generated elements). Therefore, extracting the minimum principal strain amplitudes of these elements in the three-dimensional simulation results more comprehensively understands the mechanical response of these elements during tire rolling.

[0028] According to one embodiment of the present invention, in S4, the calculation of the rubber compressive strain amplitude near the shoulder carcass includes the following steps:

[0029] S41, counting the maximum value max and the minimum value min of the minimum principal strain amplitude of each unit and the three-dimensional unit generated by rotation;

[0030] S42, minimum principal strain amplitude of the element = max-min;

[0031] S43, counting the minimum principal strain amplitude of each unit in the unit set;

[0032] S44, defining the shoulder carcass delamination durability evaluation index as the maximum value of the minimum principal strain amplitude in step S43;

[0033] S45. The unit position where the maximum value of the minimum principal strain amplitude is located is the starting point of shoulder carcass delamination damage.

[0034] This technical solution evaluates the risk of shoulder carcass delamination by extracting and analyzing the minimum principal strain amplitude of key units in the finite element analysis results. Specifically, step S41 is used to determine the maximum and minimum strains experienced by each unit during the rolling process of the tire, so as to solve the strain variation range of the unit; step S42 calculates the minimum principal strain amplitude of each unit, that is, the difference between the maximum and minimum strains experienced by the unit during the rolling process of the tire, which reflects the strain variation amplitude of the unit under periodic loading and is an important indicator for evaluating material fatigue and damage accumulation; step S43 summarizes all selected units and calculates the minimum principal strain amplitude of each unit, which is used to solve the strain distribution of the entire shoulder carcass area, so as to identify the area most prone to delamination; step S44 uses the maximum value of the minimum principal strain amplitude of all units in the unit set as an evaluation index for the delamination durability of the shoulder carcass, which represents the maximum value of the strain variation amplitude in the shoulder carcass area, and is therefore also the area most prone to delamination; step S45 determines the specific location where the shoulder carcass delamination damage occurs, that is, the unit where the minimum principal strain amplitude is the maximum value, which is the area that needs special attention during tire design and optimization because the material in this area is most susceptible to damage and destruction.

[0035] According to one embodiment of the present invention, in S5, the evaluation of shoulder carcass delamination index among multiple structural schemes includes the following steps:

[0036] S51. For different structural design schemes, the shoulder carcass delamination durability evaluation index is calculated respectively to obtain the maximum value of the minimum principal strain amplitude;

[0037] S52, ranking the durability evaluation index obtained in step S51 among the structural schemes;

[0038] S53. The structural solution with the smallest evaluation index for shoulder carcass delamination is the best solution for improving shoulder carcass delamination damage of a load-bearing radial tire.

[0039] In the present technical solution, the maximum value of the minimum principal strain amplitude in step S51 is used as an evaluation index for the shoulder carcass delamination durability, because it reflects the maximum strain variation range of the shoulder carcass region of the tire under cyclic loads. By calculating this index under different structural design schemes, the performance of each scheme in terms of shoulder carcass delamination durability is quantitatively evaluated; step S52 intuitively compares the advantages and disadvantages of each scheme in terms of shoulder carcass delamination durability by sorting the durability evaluation indexes of different structural design schemes; the sorting result helps to quickly identify the best and worst performing schemes, and provide guidance for subsequent optimization design; the structural scheme with the smallest evaluation index for shoulder carcass delamination in step S53 means that this scheme performs best in terms of shoulder carcass delamination durability, and is therefore the best solution for improving shoulder carcass delamination damage of load-bearing radial tires, which helps to reduce the risk of shoulder carcass delamination in actual use of the tire and improve the safety and service life of the tire.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] (1) The performance of shoulder carcass delamination damage of load-bearing radial tires is evaluated by establishing a tire simulation model, performing simulation calculations under vertical load conditions, extracting shoulder carcass delamination damage indicators, calculating rubber compression strain amplitude, and evaluating shoulder carcass delamination indicators of different design schemes;

[0042] (2) Determine the durability evaluation index for shoulder carcass delamination damage as the maximum value of the minimum principal strain amplitude of the rubber unit in the dangerous area; effectively evaluate the performance differences of shoulder carcass delamination damage between schemes with different structures, quickly optimize the design scheme, and provide support for improving the overall life of the tire. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a diagram of shoulder carcass delamination damage in the prior art.

[0044] Figure 2 It is the material distribution diagram of the tire design of the present invention.

[0045] Figure 3 It is a finite element discrete grid model diagram of the present invention.

[0046] Figure 4 It is a diagram of the geometry and strain calculation results of the tire inflation state of the present invention.

[0047] Figure 5 It is a diagram of the geometry and strain calculation results of the tire after loading of the present invention.

[0048] Figure 6 It is one of the analysis unit set diagrams of shoulder carcass delamination damage of the present invention.

[0049] Figure 7 It is a diagram of the maximum and minimum values ​​of the minimum principal strain amplitude of the present invention.

[0050] Figure 8 This is the second analysis unit set diagram of shoulder carcass delamination damage of the present invention.

[0051] In the figure: 1. Unit set; 2. Starting point. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are 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 creative work are within the scope of protection of the present invention.

[0053] Example 1

[0054] like Figure 1 As shown, this embodiment provides a method for simulating and evaluating shoulder carcass delamination damage performance based on minimum principal strain amplitude, comprising the following steps:

[0055] S1. Establishment of tire simulation model: discretize the tire design material distribution map into a finite element simulation model;

[0056] S2. Simulation calculation of tire vertical load conditions: through simulation calculation, the three-dimensional geometry, stress and strain results of the tire model under vertical load conditions are obtained;

[0057] S3. Extraction of shoulder carcass delamination damage index: Mechanical analysis shows that the periodic compression of the rubber unit near the shoulder carcass is the mechanical cause of the damage. The minimum principal strain amplitude is used to evaluate the compression strain of the rubber near the shoulder carcass.

[0058] S4. Calculation of the rubber compressive strain amplitude near the shoulder carcass: The minimum principal strain amplitude is defined as the difference between the maximum and minimum minimum principal strains of the rubber unit near the shoulder carcass after one rolling of the tire, which is used to determine that the minimum principal strain amplitude of the rubber unit near the shoulder carcass is an evaluation index for shoulder carcass delamination;

[0059] S5. Evaluation of shoulder carcass delamination index among multiple structural schemes: Simulate and calculate tires of different designs respectively to obtain the minimum principal strain amplitude of the rubber unit near the shoulder carcass, which is the evaluation index of shoulder carcass delamination; the structural scheme with the smallest evaluation index of shoulder carcass delamination is the best scheme.

[0060] This technical solution is used to evaluate the performance of shoulder carcass delamination damage of load-bearing radial tires by establishing a tire simulation model, performing simulation calculations under vertical load conditions, extracting shoulder carcass delamination damage indicators, calculating rubber compression strain amplitude, and evaluating shoulder carcass delamination indicators of different design schemes. Specifically, step S1 discretizes the complex tire structure into a numerical model processed by a computer for subsequent mechanical analysis; step S2 applies a vertical load consistent with the actual working condition to the finite element model, obtains the three-dimensional geometry, stress distribution and strain results of the tire under load through simulation calculation, and simulates the stress conditions of the tire in actual use; step S3 The rubber unit near the shoulder carcass is easily damaged under cyclic compression, and the minimum principal strain amplitude is used as an indicator to evaluate the rubber compression strain near the shoulder carcass. The minimum principal strain amplitude can reflect the fatigue of the material under cyclic loading. The degree of fatigue accumulation; Step S4 defines the minimum principal strain amplitude as the difference between the maximum and minimum values ​​of the minimum principal strain of the rubber unit concerned near the shoulder carcass when the tire rolls one circle. The larger the difference, the more severe the compression deformation of the rubber unit, thereby increasing the risk of delamination damage; Step S5 evaluates the delamination damage risk of each scheme by comparing the simulation calculation results of tires with different design schemes under the same conditions, that is, the minimum principal strain amplitude of the rubber unit near the shoulder carcass, and selects the design scheme with the smallest shoulder carcass delamination evaluation index as the best scheme, because it has a lower delamination risk in theory.

[0061] In addition, the above-mentioned simulation evaluation method for shoulder carcass delamination damage performance based on minimum principal strain amplitude according to the present invention also has the following additional technical features:

[0062] According to one embodiment of the present invention, in S1, establishing the tire simulation model includes the following steps:

[0063] S11. Use 2D drawing software to draw a material distribution map including the inner and outer contours of the tire, the skeleton material, the internal rubber components and the component boundary lines in a 1:1 ratio;

[0064] S12, importing the drawn material distribution map into finite element meshing software, performing finite element meshing on the tire material distribution map, and generating a two-dimensional axisymmetric finite element model;

[0065] S13, define the unit type in the two-dimensional axisymmetric finite element model, wherein the skeleton material unit type is defined as SFMGAX1, and the rubber material unit type is defined as CGAX4H and CGAX3H;

[0066] S14. Referring to the actual working conditions of the tire, the tire simulation model is equipped with a rim and a uniformly distributed pressure consistent with the air pressure is applied, and the finite element analysis software Abaqus is submitted for two-dimensional inflation simulation calculation.

[0067] This technical solution uses the finite element analysis software Abaqus to simulate the actual physical properties and working environment of the tire to predict the performance of the tire under different working conditions. Specifically, step S11 uses two-dimensional drawing software to draw a material distribution map of the tire, which is the basis for establishing a simulation model to ensure that the model can accurately reflect the geometric shape and material composition of the tire, including the inner and outer contours, skeleton materials, internal rubber components and component boundaries; the finite element grid of step S12 is the basic unit of simulation analysis, which discretizes the continuum into a finite number of units, each unit is connected by nodes, and through reasonable grid division, it simulates the complex structure and material properties of the tire while ensuring computational efficiency and accuracy; step S13 defines the unit type in the two-dimensional axisymmetric finite element model, which is selected according to the material properties and mechanical properties of different parts of the tire. The unit type (such as SFMGAX1) of the skeleton material (such as the cord) is usually used to simulate the mechanical behavior of the fiber-reinforced material, while the unit type of the rubber material (such as CGAX4H and CGAX3H) is used to simulate the nonlinearity, viscoelasticity and large deformation characteristics of the rubber material; step S14 refers to the actual working condition of the tire, assembles the rim to the tire simulation model, applies a uniformly distributed pressure consistent with the air pressure, and submits it to the finite element analysis software Abaqus for two-dimensional inflation simulation calculation to simulate the inflation process of the tire in actual use; by applying air pressure and constraints, calculates the geometric shape and internal stress distribution of the tire in the inflated state.

[0068] According to one embodiment of the present invention, in S2, the tire vertical load condition simulation calculation includes the following steps:

[0069] S21, using the SMG technology in the finite element analysis software Abaqus, rotating the two-dimensional finite element mesh obtained in the above S14 to generate a three-dimensional finite element mesh model;

[0070] S22, transferring the two-dimensional finite element inflation analysis result obtained in the above S14 to the three-dimensional finite element mesh model through the SRT technology in the finite element analysis software Abaqus;

[0071] S23. According to the actual load during the use of the tire, a vertical force is applied to the three-dimensional tire model, and the Abaqus standard solver of the finite element analysis software is submitted to perform loading simulation calculations to obtain the three-dimensional loading geometry and three-dimensional stress and strain distribution of the tire simulation model.

[0072] This technical solution uses the SMG and SRT technologies in the Abaqus software, combined with finite element analysis technology, to quickly and accurately construct a three-dimensional tire model, and transfer the two-dimensional inflation analysis results to the three-dimensional model, thereby simulating the stress conditions of the tire under actual working conditions, providing important support for tire performance evaluation and safety analysis. Specifically, step S21 uses the SMG technology in Abaqus to rotate the two-dimensional finite element mesh to generate a three-dimensional finite element mesh model. By rotating the two-dimensional mesh, a three-dimensional tire model is quickly and accurately constructed to provide a basis for subsequent simulation analysis; step S22 uses the SRT technology in Abaqus to transfer the results of the two-dimensional inflation analysis (such as the tire shape and internal stress distribution after inflation) to the three-dimensional model, thereby avoiding the need to repeat the three-dimensional inflation analysis and improving the simulation efficiency; step S23 is a key step in simulating the stress conditions of the tire under actual working conditions. By applying a vertical force consistent with the actual load, the stress conditions of the tire under driving, braking, cornering and other working conditions are simulated. The Abaqus standard solver is a powerful finite element solver that can handle various complex mechanical problems, including nonlinear, large deformation and other problems. By submitting the solver for calculation, the three-dimensional loading geometry and three-dimensional stress and strain distribution of the tire under vertical load conditions are obtained, providing an important basis for evaluating the performance and safety of the tire.

[0073] According to one embodiment of the present invention, in S3, the shoulder carcass delamination damage index extraction includes the following steps:

[0074] S31, in the two-dimensional simulation results, 10 elements of the shoulder pad rubber adjacent to the shoulder carcass and where carcass delamination occurs are selected along the carcass cord direction at the shoulder position, and an element set 1 is established to include the position information of the shoulder carcass delamination occurring;

[0075] S32. In the three-dimensional simulation results, extract and record the minimum principal strain amplitude of each unit in the unit set 1 constructed in step S31 and the three-dimensional generated unit of the unit in the circumferential direction.

[0076] This technical solution uses the results of finite element analysis to select the elements in the key areas and extract their minimum principal strain amplitudes to evaluate the risk of shoulder carcass delamination. Specifically, step S31 locates and analyzes the areas where shoulder carcass delamination is most likely to occur. The shoulder position is one of the places where the tire is subjected to the maximum stress and strain. By selecting 10 elements and establishing an element set 1, focus on these key areas and extract their mechanical response data; step S32 is used to quantify the risk of shoulder carcass delamination. The minimum principal strain amplitude is an important indicator for evaluating material fatigue and damage accumulation because it reflects the difference between the maximum and minimum strains of the material under cyclic loading. By extracting the minimum principal strain amplitudes of these elements, their strain changes during tire rolling are evaluated and whether they are prone to delamination are predicted. In addition, since the tire is a three-dimensional structure, the elements selected in the two-dimensional simulation results will have multiple corresponding elements in the three-dimensional space (i.e., three-dimensional generated elements). Therefore, extracting the minimum principal strain amplitudes of these elements in the three-dimensional simulation results more comprehensively understands the mechanical response of these elements during tire rolling.

[0077] According to one embodiment of the present invention, in S4, the calculation of the rubber compressive strain amplitude near the shoulder carcass includes the following steps:

[0078] S41, counting the maximum value max and the minimum value min of the minimum principal strain amplitude of each unit and the three-dimensional unit generated by rotation;

[0079] S42, minimum principal strain amplitude of the element = max-min;

[0080] S43, counting the minimum principal strain amplitude of each unit in unit set 1;

[0081] S44, defining the shoulder carcass delamination durability evaluation index as the maximum value of the minimum principal strain amplitude in step S43;

[0082] S45. The unit position where the maximum value of the minimum principal strain amplitude is located is the starting point 2 of the shoulder carcass delamination damage.

[0083] This technical solution evaluates the risk of shoulder carcass delamination by extracting and analyzing the minimum principal strain amplitude of key units in the finite element analysis results. Specifically, step S41 is used to determine the maximum and minimum strains experienced by each unit during the rolling process of the tire, so as to solve the strain variation range of the unit; step S42 calculates the minimum principal strain amplitude of each unit, that is, the difference between the maximum and minimum strains experienced by the unit during the rolling process of the tire, which reflects the strain variation amplitude of the unit under periodic loading and is an important indicator for evaluating material fatigue and damage accumulation; step S43 summarizes all selected units and calculates the minimum principal strain amplitude of each unit, which is used to solve the strain distribution of the entire shoulder carcass area, so as to identify the area most prone to delamination; step S44 uses the maximum value of the minimum principal strain amplitude of all units in unit set 1 as an evaluation index for the delamination durability of the shoulder carcass, representing the unit with the largest strain variation amplitude in the shoulder carcass area, and therefore also the area most prone to delamination; step S45 determines the specific location where the shoulder carcass delamination damage occurs, that is, the unit where the minimum principal strain amplitude is maximum, which is the area that needs special attention during tire design and optimization because the material in this area is most susceptible to damage and destruction.

[0084] According to one embodiment of the present invention, in S5, the evaluation of shoulder carcass delamination index among multiple structural schemes includes the following steps:

[0085] S51. For different structural design schemes, the shoulder carcass delamination durability evaluation index is calculated respectively to obtain the maximum value of the minimum principal strain amplitude;

[0086] S52, ranking the durability evaluation index obtained in step S51 among the structural schemes;

[0087] S53. The structural solution with the smallest evaluation index for shoulder carcass delamination is the best solution for improving shoulder carcass delamination damage of a load-bearing radial tire.

[0088] In the present technical solution, the maximum value of the minimum principal strain amplitude in step S51 is used as an evaluation index for the shoulder carcass delamination durability, because it reflects the maximum strain variation range of the shoulder carcass region of the tire under cyclic loads. By calculating this index under different structural design schemes, the performance of each scheme in terms of shoulder carcass delamination durability is quantitatively evaluated; step S52 intuitively compares the advantages and disadvantages of each scheme in terms of shoulder carcass delamination durability by sorting the durability evaluation indexes of different structural design schemes; the sorting result helps to quickly identify the best and worst performing schemes, and provide guidance for subsequent optimization design; the structural scheme with the smallest evaluation index for shoulder carcass delamination in step S53 means that this scheme performs best in terms of shoulder carcass delamination durability, and is therefore the best solution for improving shoulder carcass delamination damage of load-bearing radial tires, which helps to reduce the risk of shoulder carcass delamination in actual use of the tire and improve the safety and service life of the tire.

[0089] Example 2

[0090] Taking the 16.00R25 radial tire as an example, the tire material distribution diagram is drawn using the 2D drawing software Zhongwang CAD. Figure 2 As shown, it is necessary to include the inner contour line, outer contour line and dividing lines of the various components of the tire.

[0091] S1. Import the CAD model into the meshing software Hypermesh for finite element mesh discretization. The discrete finite element mesh size is defined as about 10 mm according to the tire size. Figure 3 As shown, the triangular mesh is assigned a 3-node axisymmetric hybrid unit, the quadrilateral mesh is assigned a 4-node axisymmetric hybrid unit, and the reinforcing cord is assigned an axisymmetric shell unit using the rebar model.

[0092] S2. Assemble and inflate the tire 2D finite element model. Set the air pressure to 1250 kPa consistent with the actual working conditions. Submit the simulation analysis to obtain the geometry of the tire inflated state and the internal stress distribution results, such as Figure 4 shown.

[0093] S3. Generate a three-dimensional tire finite element model through Abaqus SMG technology and SRT technology, and transfer the stress and strain results of the two-dimensional axisymmetric tire finite element model to the three-dimensional tire finite element model.

[0094] S4. Apply a 12-ton vertical load to the three-dimensional finite element model using the Abaqus finite element analysis software and submit it to the Abaqus standard solver for calculation. Complete the calculation and obtain the three-dimensional loading geometry and internal stress and strain results of the tire, such as Figure 5 shown.

[0095] S5. Select the shoulder cushion rubber unit set 1 adjacent to the shoulder carcass. In this example, a total of 12 units are selected as the index extraction objects. The position of unit set 1 is as follows: Figure 6 shown.

[0096] S6. For the first unit in unit set 1, if Figure 6 As shown, extract the corresponding whole-cycle unit, and obtain the minimum and maximum values ​​of the minimum principal strain index of the whole-cycle unit, such as Figure 7 As shown, the minimum principal strain min=-0.2067, and the maximum principal strain max=-0.02103.

[0097] S7, the minimum principal strain amplitude at the location of the first unit of the unit set 1 = (-0.02103) - (-0.2067) = 0.18567;

[0098] S8. Calculate the minimum principal strain amplitude for all units in unit set 1, where the unit with the largest minimum principal strain amplitude is located. Figure 8 As shown, its value is 0.1922.

[0099] Through the above simulation analysis, the durability evaluation index of the shoulder carcass delamination damage of this structural design scheme, the maximum value of the minimum principal strain amplitude at the location of unit set 1 is 0.1922.

[0100] Example 3

[0101] The structural design scheme in Example 2 is improved and designed, and S1 to S8 in Example 1 are repeated to obtain the durability evaluation index of the shoulder carcass delamination damage of the design scheme in Example 2. The maximum value of the minimum principal strain amplitude at the location of unit set 1 is 0.1838.

[0102] Compared with the maximum value of 0.1922 of the minimum principal strain amplitude of the durability evaluation index at the location of unit set 1 in Example 2, the maximum value of 0.1838 of the minimum principal strain amplitude at the location of unit set 1 in Example 3 is smaller, and the risk of shoulder carcass delamination in the tire structure scheme of Example 3 is lower than that of Example 2, and Example 3 is the best scheme.

[0103] The implementation examples and related drawings described in the present invention do not limit the product form and style of the present invention. There are other detailed details, which are explained here.

[0104] For example, the tire material distribution map involved in the simulation analysis is a load-carrying radial tire of any size and specification;

[0105] For example, the mesh size of the tire simulation model is any size that fits within the computer memory and obtains the calculation results;

[0106] For example, the element type in the tire finite element simulation model is any element type that satisfies axisymmetric calculations;

[0107] For example, when selecting unit set 1 to participate in the extraction of the durability index, the unit layer closest to the shoulder carcass is also a multi-layer unit that meets the requirements, and the number of units in unit set 1 also changes accordingly.

[0108] In summary, the present invention discloses a simulation evaluation method for tire durability, which aims to determine the durability evaluation index of the shoulder carcass delamination performance of a load-bearing radial tire, optimize the design scheme, and improve the service life of the tire product. Through simulation analysis, the present invention determines that the periodic compression of the rubber unit adjacent to the shoulder carcass is the mechanical cause of the delamination damage, and determines the minimum principal strain amplitude of the shoulder pad rubber unit adjacent to the shoulder carcass as an evaluation index. The market has verified that the evaluation index is accurate and reliable, solves the evaluation problem of the shoulder carcass delamination performance, and effectively supports the research and development of load-bearing radial tire products.

[0109] Although the present invention is described in detail by referring to the accompanying drawings and in combination with the preferred embodiments, the present invention is not limited thereto. Without departing from the spirit and essence of the present invention, a person of ordinary skill in the art may make various equivalent modifications or substitutions to the embodiments of the present invention, and these modifications or substitutions shall be within the scope of the present invention. Any person of ordinary skill in the art may easily think of changes or substitutions within the technical scope disclosed by the present invention, and these shall be within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A simulation evaluation method for shoulder carcass delamination damage performance based on minimum principal strain amplitude, characterized in that: The steps include: S1. Establishment of tire simulation model: discretize the tire design material distribution map into a finite element simulation model; S2. Simulation calculation of tire vertical load conditions: through simulation calculation, the three-dimensional geometry, stress and strain results of the tire model under vertical load conditions are obtained; S3. Extraction of shoulder carcass delamination damage index: Mechanical analysis shows that the periodic compression of the rubber unit near the shoulder carcass is the mechanical cause of the damage. The minimum principal strain amplitude is used to evaluate the compression strain of the rubber near the shoulder carcass. S4. Calculation of the rubber compressive strain amplitude near the shoulder carcass: The minimum principal strain amplitude is defined as the difference between the maximum and minimum minimum principal strains of the rubber unit near the shoulder carcass after one rolling of the tire, which is used to determine that the minimum principal strain amplitude of the rubber unit near the shoulder carcass is an evaluation index for shoulder carcass delamination; S5. Evaluation of shoulder carcass delamination index among multiple structural schemes: Simulation calculations are performed on tires of different designs to obtain the minimum principal strain amplitude of the rubber unit near the shoulder carcass, i.e., the evaluation index of shoulder carcass delamination; the structural scheme with the smallest evaluation index of shoulder carcass delamination is the best scheme; In S1, the tire simulation model is established by the following steps: S11. Use 2D drawing software to draw a material distribution map including the inner and outer contours of the tire, the skeleton material, the internal rubber components and the component boundary lines in a 1:1 ratio; S12, importing the drawn material distribution map into finite element meshing software, performing finite element meshing on the tire material distribution map, and generating a two-dimensional axisymmetric finite element model; S13, define the unit type in the two-dimensional axisymmetric finite element model, wherein the skeleton material unit type is defined as SFMGAX1, and the rubber material unit type is defined as CGAX4H and CGAX3H; S14, referring to the actual working condition of the tire, by assembling a rim on the tire simulation model and applying a uniform pressure consistent with the air pressure, submitting the finite element analysis software Abaqus to perform two-dimensional inflation simulation calculation; In S2, the tire vertical load condition simulation calculation includes the following steps: S21, using the SMG technology in the finite element analysis software Abaqus, rotating the two-dimensional finite element mesh obtained in the above S14 to generate a three-dimensional finite element mesh model; S22, transferring the two-dimensional finite element inflation analysis result obtained in the above S14 to the three-dimensional finite element mesh model through the SRT technology in the finite element analysis software Abaqus; S23, applying a vertical force to the three-dimensional tire model according to the actual load during the use of the tire, submitting the Abaqus standard solver of the finite element analysis software to perform loading simulation calculation, and obtaining the three-dimensional loading geometry and three-dimensional stress and strain distribution of the tire simulation model; In S3, the shoulder carcass delamination damage index extraction includes the following steps: S31. In the two-dimensional simulation results, 10 elements of the shoulder pad rubber adjacent to the shoulder carcass and where carcass delamination occurs are selected along the carcass cord direction at the shoulder position, and the position information of the shoulder carcass delamination occurs is included by establishing an element set (1); S32, in the three-dimensional simulation results, extract and record the minimum principal strain amplitude of each unit in the unit set (1) created in step S31 and the three-dimensional generated unit of the unit in the circumferential direction; In S4, the calculation of the rubber compressive strain amplitude near the shoulder carcass includes the following steps: S41, counting the maximum value max and the minimum value min of the minimum principal strain amplitude of each unit and the three-dimensional unit generated by rotation; S42, minimum principal strain amplitude of the element = max-min; S43, counting the minimum principal strain amplitude of each unit in the unit set (1); S44, defining the shoulder carcass delamination durability evaluation index as the maximum value of the minimum principal strain amplitude in step S43; S45, the unit position where the maximum value of the minimum principal strain amplitude is located is the starting point of shoulder carcass delamination damage (2); In S5, the evaluation of shoulder carcass delamination index among multiple structural schemes includes the following steps: S51. For different structural design schemes, the shoulder carcass delamination durability evaluation index is calculated respectively to obtain the maximum value of the minimum principal strain amplitude; S52, ranking the durability evaluation index obtained in step S51 among the structural schemes; S53. The structural solution with the smallest evaluation index for shoulder carcass delamination is the best solution for improving shoulder carcass delamination damage of a load-bearing radial tire.

Images