Tire design method for improving tire road holding based on finite element analysis

Abstract

The invention relates to the technical field of tire production, in particular to a tire design method for improving the road holding force of a tire based on finite element analysis, and the method comprises the following steps: establishing a parameterized 3D tire model; setting a change gradient interval of the sidewall width and establishing a correlation formula; performing grid division on the parameterized 3D tire model; superposing constraint conditions on the parameterized 3D tire model; adjusting the sidewall width according to the change gradient interval, and synchronously adjusting the groove depth; generating a new tire model; performing dynamic rolling simulation, and extracting a grounding pressure distribution cloud picture; and outputting parameters of the 3D tire model. According to the method, through deep fusion of parametric modeling and finite element simulation, namely through accurate parameter matching, the tire structure defects are reduced, the risk of local excessive wear is reduced, and a foundation is laid for prolonging the service life; and through an orthogonal test and a stratified sampling strategy, the parameter optimization efficiency is improved, invalid research and development links are reduced, and the research and development period is shortened.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tire production, and particularly relates to a tire design method for improving tire grip based on finite element analysis. BACKGROUND

[0002] As the only component of a vehicle in contact with the road, the tire grip directly affects the braking, acceleration and handling safety of the vehicle, and the service life is related to the user's use cost and resource utilization efficiency. The balance of the two is the core challenge of tire design. With the development of finite element analysis (FEA) technology, some enterprises have begun to introduce simulation tools to assist in design, but the existing methods still have shortcomings: the degree of parametric modeling is low, and it is difficult to coordinate the parameters of the sidewall and the groove; the meshing is not targeted, and the precision of the contact area is insufficient or the redundant calculation of the non-critical area leads to low simulation efficiency; the adaptability of multiple working conditions is not considered, and the simulation results under single road or load conditions are difficult to cover the actual complex driving scenarios. These problems lead to large deviations between simulation and actual measurement, making it difficult to effectively replace physical testing and restricting the improvement of research and development efficiency and the accuracy of performance optimization.

[0003] Therefore, how to provide a tire design method for improving tire grip so as to achieve the coordinated improvement of tire grip and service life while shortening the research and development cycle is a technical problem to be solved by those skilled in the art. SUMMARY

[0004] The purpose of the present application is to provide a tire design method for improving tire grip based on finite element analysis to solve the problem that the existing technology cannot achieve the coordinated improvement of tire grip and service life while shortening the research and development cycle.

[0005] The present application provides a tire design method for improving tire grip based on finite element analysis, comprising:

[0006] Obtaining the tire specifications of a tire to be designed and establishing a parameterized 3D tire model according to the tire specifications;

[0007] Setting a change gradient interval of the sidewall width and establishing a correlation formula about the sidewall width and the groove depth;

[0008] Meshing the parameterized 3D tire model, using a first mesh density to construct the contact area in the parameterized 3D tire model, and using a second mesh density to construct the non-contact area in the parameterized 3D tire model, and the first mesh density is greater than the second mesh density;

[0009] Obtaining the constraint conditions of the tire in the vehicle motion process, and superimposing the constraint conditions on the parameterized 3D tire model;

[0010] According to the change gradient interval, the sidewall width is adjusted, and according to the correlation formula, the groove depth is synchronously adjusted;

[0011] The adjusted sidewall width and groove depth are substituted into the parameterized 3D tire model to generate a new parameterized 3D tire model;

[0012] The working condition load spectrum of the tire is obtained, and dynamic rolling simulation is performed according to the working condition load spectrum and the new parameterized 3D tire model, and a ground pressure distribution cloud diagram is extracted;

[0013] According to the ground pressure distribution cloud diagram, the tire grip is calculated, and in response to the tire grip meeting the preset requirements, the new parameterized 3D tire model is output.

[0014] As a preferred technical solution of the tire design method based on finite element analysis to improve the tire grip, the tire specifications include: tire width, flat ratio, tire structure type, rim diameter, load index, and speed level;

[0015] The constraint conditions include: inflation pressure loading, contact boundary conditions, and temperature boundary conditions.

[0016] As a preferred technical solution of the tire design method based on finite element analysis to improve the tire grip, the correlation formula about the sidewall width and the groove depth is obtained by fitting the finite element simulation data, including:

[0017] Determine the independent variables, dependent variables and constraint conditions in the correlation formula; the independent variables are the sidewall width, the dependent variables are the groove depth, the groove bending degree and the sidewall inclination angle;

[0018] Using orthogonal test method, multiple gradient levels are set for the independent variables and the dependent variables to screen the historical data, and a typical parameter combination sample covering the whole variable space is generated;

[0019] According to the typical parameter combination sample, a 3D model is constructed, and a finite element simulation software simulates the tire driving state, and extracts performance indicators in the simulation process, wherein the performance indicators include: ground pressure uniformity, groove stress and drainage path length;

[0020] According to the importance of each performance indicator, different weights are set for each performance indicator, different typical parameter combination samples under the same sidewall width are scored, and the combination of the highest score of the groove depth, the groove bending degree and the sidewall inclination angle is selected to form a mapping relationship table;

[0021] Curve fitting is performed on the data in the mapping relationship table, the basic functions of the independent variables and each dependent variable are respectively established, the interactive item correction parameter cooperative relationship is introduced, and the constraint conditions are embedded;

[0022] The historical data not involved in the fitting are substituted into the base function respectively to obtain simulation results, a weighted sum of relative errors of each dependent variable of the simulation results and actual simulation data in the historical data is calculated, and in response to the error being greater than or equal to an error threshold, the sample is supplemented and refitted until the error is less than the error threshold.

[0023] As a preferred technical solution of the tire design method for improving tire grip based on finite element analysis, the inflation pressure loading adopts a step-by-step loading mode, including:

[0024] The tire is loaded at an initial pressure to eliminate the initial gap of the model; the initial pressure is a preset percentage of the target pressure;

[0025] The pressure loading process between the initial pressure and the target pressure is divided into multiple loading periods;

[0026] For a single loading period, the profile deformation of the tire during the loading process is obtained in real time, in response to the profile deformation being greater than or equal to a preset deformation, it is determined that the model may have an abnormality in the current loading step, and the loading needs to be paused and the model is checked; in response to the profile deformation being less than the preset deformation, it is determined that the model is running normally in the current loading step, and the next loading period can be started until the target pressure is reached.

[0027] As a preferred technical solution of the tire design method for improving tire grip based on finite element analysis, the temperature boundary condition adopts a thermal-mechanical coupling analysis mode, taking the friction heat and material deformation heat generated during tire rolling as internal heat sources, and setting the convection heat dissipation coefficients of the tread and the sidewall to simulate the external heat dissipation environment.

[0028] As a preferred technical solution of the tire design method for improving tire grip based on finite element analysis, the calculation of the tire grip according to the ground pressure distribution cloud map includes: calculating the longitudinal grip and the lateral grip of the tire respectively, the longitudinal grip is calculated based on the ground pressure distribution under the braking or driving working condition, and the lateral grip is calculated based on the ground pressure distribution under the steering working condition.

[0029] As a preferred technical solution of the tire design method for improving tire grip based on finite element analysis, in the mesh division process, the first mesh density of the tire contact area adopts an adaptive encryption mechanism, specifically including: first, dividing the base mesh according to the initial mesh size, and then according to the pre-calculated ground pressure gradient distribution of the dynamic rolling simulation, the area with a pressure gradient exceeding a preset pressure gradient threshold is encrypted again, the mesh size after encryption is not greater than 50% of the base mesh size, and the edge of the encrypted area is realized by a transition unit to realize the smooth transition of the mesh density.

[0030] As the preferred technical scheme of the tire design method for improving tire grip based on finite element analysis, the setting of the contact boundary condition comprises a multi-working condition contact parameter switching mechanism, specifically: corresponding friction coefficient models and contact parameters are preset for dry ground, wet ground and ice and snow road surfaces, and in the dynamic rolling simulation process, the matched contact parameters can be automatically called according to the road surface type parameters in the working condition load spectrum.

[0031] As the preferred technical scheme of the tire design method for improving tire grip based on finite element analysis, when the orthogonal test method generates a typical parameter combination sample, a stratified sampling strategy is adopted, specifically including: the variation gradient interval of the sidewall width is divided into a plurality of subintervals, sample points are selected in each subinterval according to a preset proportion, the sample distribution uniformity of each subinterval is ensured, and the number of sample points is distributed in proportion to the sensitivity coefficient of the sidewall width in the subinterval to performance, and the sensitivity coefficient is determined through a single-factor simulation test in the early stage.

[0032] Compared with the prior art, the beneficial effects of the present application are that the present application constructs a closed-loop design system of "structure parameter coordinated adjustment-multi-working condition performance simulation-accurate grip force evaluation" through the deep integration of parameterized modeling and finite element simulation, reduces tire structure defects through accurate parameter matching, reduces the risk of local excessive wear, and lays a foundation for prolonging the service life; secondly, the orthogonal test and stratified sampling strategy improve the parameter optimization efficiency, reduce the invalid research and development links, and gradually shorten the research and development cycle. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 The step flowchart of the tire design method for improving tire grip based on finite element analysis of the embodiments of the present application. DETAILED DESCRIPTION

[0034] The features and exemplary embodiments of various aspects of the present application will be described in detail below, in order to make the purposes, technical solutions and advantages of the present application more clear and apparent, the present application will be further described in detail below in combination with the drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, but not to limit the present application. The present application can be implemented without some of these specific details by those skilled in the art. The following description of the embodiments is only to provide a better understanding of the present application by showing examples of the present application.

[0035] It is to be noted that, in the present document, relational terms such as first and second and the like can be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises... a" does not, without more constraints, exclude the presence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0036] Referring to Figure 1 As shown in the figure, it is the step flow of the tire design method for improving tire grip based on finite element analysis according to an embodiment of the present application, which comprises:

[0037] Step S1, obtaining the tire specification of the tire to be designed and establishing a parameterized 3D tire model according to the tire specification;

[0038] Step S2, setting the variation gradient interval of the sidewall width and establishing the correlation formula about the sidewall width and the groove depth;

[0039] Step S3, meshing the parameterized 3D tire model, using the first mesh density to construct for the contact area in the parameterized 3D tire model, using the second mesh density to construct for the non-contact area in the parameterized 3D tire model, and the first mesh density is greater than the second mesh density;

[0040] Step S4, obtaining the constraint condition of the tire in the vehicle motion process, and superimposing the constraint condition on the parameterized 3D tire model;

[0041] Step S5, adjusting the sidewall width according to the variation gradient interval, and adjusting the groove depth synchronously according to the correlation formula;

[0042] Step S6, substituting the adjusted sidewall width and groove depth into the parameterized 3D tire model to generate a new parameterized 3D tire model;

[0043] Step S7, obtaining the working condition load spectrum of the tire and performing dynamic rolling simulation according to the working condition load spectrum and the new parameterized 3D tire model, and extracting the ground pressure distribution cloud picture;

[0044] Step S8, calculating the tire grip according to the ground pressure distribution cloud picture, responding to the tire grip meeting the preset requirement, and outputting the new parameterized 3D tire model.

[0045] In implementation, according to the specification of the tire to be designed (such as 205 / 55R16), a parameterized model is constructed by using CATIA, UG or other three-dimensional modeling software, wherein the model contains substructures such as tread, sidewall, bead, belt, etc., and the sidewall width and groove depth are editable parameters. According to the tire specification, the sidewall width variation gradient interval (such as 180-195mm) is determined, and the correlation formula of the sidewall width and the groove depth (such as groove depth = 0.1 x sidewall width - 10) is fitted by using finite element simulation data to ensure the coordinated adjustment of the two. The mesh is divided by using the Hypermesh software, the first grid density (such as 5mm hexahedral unit) is used for the contact area (the contact part of the tread and the road surface), the second grid density (such as 10mm tetrahedral unit) is used for the non-contact area (the upper part of the sidewall, the bead, etc.), and the density is smoothly transitioned through the transition unit. The constraint is applied by using the Abaqus software. The sidewall width is adjusted according to the gradient interval (preferably, the gradient interval is set to 180mm→185mm→190mm), the groove depth is calculated synchronously through the correlation formula, and the new tire model is automatically generated by substituting the model. Based on the working condition load spectrum (such as vertical load 4900N, rolling speed 80km / h, steering angle 3°), dynamic rolling simulation is carried out in Abaqus, and the contact pressure distribution cloud diagram is extracted. According to the contact pressure distribution cloud diagram, the integral method is used to calculate the longitudinal (braking / driving) and lateral (steering) grip force, and if the grip force reaches the preset pressure gradient threshold (such as an increase of 15% compared with the reference), the optimal parameters (such as sidewall width 190mm, groove depth 9mm) are output.

[0046] In detail, by establishing a parameterized 3D tire model, the present application can quickly respond to the adjustment requirements of the sidewall width and the groove depth, differential mesh division can ensure the calculation accuracy of the contact area (the core area of the grip force) while reducing the number of meshes in the non-contact area, reducing the calculation load of the dynamic rolling simulation and speeding up the simulation process; the grip force is calculated in combination with the contact pressure distribution cloud diagram, which makes the performance evaluation more accurate and avoids invalid optimization caused by inaccurate evaluation, thereby shortening the development cycle.

[0047] Further, the tire specification includes: tire width, flat ratio, tire structure type, rim diameter, load index and speed level;

[0048] The constraint conditions include: inflation pressure loading, contact boundary condition and temperature boundary condition.

[0049] In implementation, the tire specification parameters are extracted from the design requirements: tire width (such as 205mm), flat ratio (55%), structure type (radial), rim diameter (16 inches), load index (91), speed level (V), and these parameters are used as the initial constraints for the construction of the 3D model (such as the tire outer diameter is determined by the width, flat ratio and rim diameter).

[0050] The setting of the constraint conditions comprises:

[0051] Air pressure loading: according to the recommended value of the tire specification (such as 240 kPa), a uniform normal pressure is applied to the inner surface of the tire by Abaqus to simulate the actual inflation state.

[0052] Contact boundary condition: the road surface is set as a rigid plane, the tread is set as a deformed body, the normal direction uses a hard contact model (no penetration), and the tangential direction uses a velocity-dependent friction model (static friction coefficient 0.85, dynamic friction coefficient 0.65).

[0053] Temperature boundary condition: the frictional heat generated by the tread and the road surface and the deformation heat generated by the carcass are set as internal heat sources, and the convection heat dissipation coefficient of the tread is set to 25 W / m 2 K, the sidewall is 18 W / m 2 K, and the ambient temperature is 25℃.

[0054] In detail, the present application ensures that the design conforms to industry standards and use scenarios by obtaining specification parameters and providing initial constraints for model construction according to the tire specification parameters, avoids rework caused by deviation of basic parameters, reduces waste and research and development period. The constraint conditions of air pressure, contact boundary, temperature, etc. are comprehensively covered to simulate the working state of the tire and improve the credibility of the simulation results, reduce the performance misjudgment caused by the disconnection between simulation and actual working conditions; through the fine setting of the constraint conditions, the grip calculation is more accurate, which provides effective guidance for structure optimization, thereby reducing the number of physical prototype tests, and further shortening the research and development period.

[0055] Further, the correlation formula related to the sidewall width and the groove depth is obtained by finite element simulation data fitting, comprising:

[0056] The independent variables, dependent variables and constraint conditions in the correlation formula are determined; the independent variables are the sidewall width, the dependent variables are the groove depth, the groove bending degree and the sidewall inclination angle;

[0057] An orthogonal test method is used to set multiple gradient levels for the independent variables and the dependent variables to screen historical data and generate typical parameter combination samples covering the entire variable space;

[0058] A 3D model is constructed according to the typical parameter combination samples, a finite element simulation software simulates the tire driving state, and performance indicators in the simulation process are extracted, wherein the performance indicators include: ground pressure uniformity, groove stress and drainage path length;

[0059] Different weights are set for each performance indicator according to the importance of each performance indicator, different typical parameter combination samples under the same sidewall width are scored, the groove depth, the groove bending degree and the sidewall inclination angle combination with the highest score are selected, and a mapping relationship table is formed;

[0060] Curve fitting is performed on the data in the mapping relationship table, basic functions of independent variables and dependent variables are respectively established, an interactive item correction parameter is introduced to modify the parameter relationship, and a constraint condition is embedded;

[0061] The historical data not participating in the fitting are respectively substituted into the basic functions to obtain simulation results, a weighted sum of relative errors of each dependent variable of the simulation results and actual simulation data in the historical data is calculated, and the weighted sum is recorded as an error, in response to the error being greater than or equal to an error threshold, the sample is supplemented to re-fit until the error is less than the error threshold.

[0062] In the embodiment of the present application, the independent variable is the sidewall width TSW, and the dependent variables are the groove depth H, the groove curvature degree R and the sidewall inclination angle θ; the constraint conditions include H≤60% of the tread thickness, R≥3mm (processing limit) and θ≥30° (structural strength).

[0063] An L18 orthogonal table is used, TSW is set to 5 levels (180-195mm, interval 3mm), H is set to 3 levels (8-10mm), R is set to 3 levels (5-8mm), and θ is set to 3 levels (30-60°), to generate 18 groups of parameter combination samples.

[0064] Modeling is performed on each group of samples, and the simulation extracts the uniformity of the ground pressure (standard deviation σ), the groove stress (σ_max) and the drainage path length (L), and records the data.

[0065] A weighted scoring method (weights: σ 40%, σ_max 35%, L 25%) is used to score the 18 groups of samples, to screen the optimal (H, R, θ) combination corresponding to each TSW, and to form a mapping table.

[0066] The data in the mapping table is fitted by the least square method, to obtain H=0.07TSW-4.9, R=0.002TSW 2 -0.65TSW+52, θ=-0.85TSW+203, an interactive item (such as an H correction item containing R and θ) is introduced, and a constraint (such as forced correction when H is greater than 10mm) is embedded.

[0067] The historical data not participating in the fitting have a groove depth H0, a groove curvature degree R0 and a sidewall inclination angle θ0 corresponding to the TSW, the historical data not participating in the fitting (such as 185mm) are substituted into the basic functions to obtain simulation results: a groove depth H1, a groove curvature degree R1 and a sidewall inclination angle θ1, a weighted sum of relative errors of each dependent variable of the simulation results and actual simulation data in the historical data is calculated, the weights of the groove depth, the groove curvature degree and the sidewall inclination angle are the same as the weights in the process of scoring the 18 groups of samples, and the calculation formula of the error W is as follows:

[0068] Error

[0069] If the weighted sum is greater than or equal to the error threshold, supplementary samples are added and refitted until the error is less than the error threshold. The value of the error threshold is determined according to the actual accuracy requirements, and it is sufficient to meet the actual situation. Preferably, in this embodiment of the invention, the error threshold is 5%.

[0070] Furthermore, this invention ensures the scientific nature of parameter coordination by fitting correlation formulas with simulation data and embedding constraints, thereby reducing performance defects caused by structural conflicts. The verification and iteration mechanism guarantees the accuracy of the formulas, making parameter adjustment more reliable and reducing the repetition of later optimizations. In turn, the standardization of the design process further shortens the R&D cycle.

[0071] Specifically, the independent and dependent variables and constraints in the correlation formula are determined, where the independent variable is the tire sidewall width, and the dependent variables are the groove depth, the degree of groove curvature, and the sidewall inclination angle.

[0072] Specifically, the inflation pressure is applied using a step-by-step method, including:

[0073] The tires are loaded with an initial pressure to eliminate initial gaps in the model; the initial pressure is a preset percentage of the target pressure.

[0074] The pressure loading process between the initial pressure and the target pressure is divided into multiple loading cycles;

[0075] For a single loading cycle, the tire's profile deformation is acquired in real time during the loading process. If the profile deformation is greater than or equal to the preset deformation, it is determined that there may be an anomaly in the model in the current loading step, and loading needs to be paused and the model checked. If the profile deformation is less than the preset deformation, it is determined that the model is running normally in the current loading step, and the next loading cycle can begin until the target pressure is reached.

[0076] In implementation, the preset percentage is set to 50% of the target pressure (e.g., 120 kPa initially for a target of 240 kPa) to eliminate the initial gap between the tire model and the rim (e.g., virtual contact caused by assembly errors). Loading is performed in steps at 20% increments (120 kPa, 168 kPa, 216 kPa, 240 kPa), with a 0.5-second pause after each step to monitor tire profile deformation (e.g., maximum radial deformation of the tire sidewall). The preset deformation value is determined based on the actual needs of the tire; meeting the actual needs is sufficient. Preferably, in this embodiment, the preset deformation value is 0.1 mm. If the target is met, loading continues; otherwise, the pause time is extended until the deformation stabilizes.

[0077] Furthermore, the constraint mechanism ensures that parameters are adjusted within a reasonable range, reducing premature wear caused by structural defects and extending the effective service life of the tire.

[0078] Specifically, the temperature boundary conditions adopt a thermo-mechanical coupling analysis mode, taking the frictional heat and material deformation heat generated during tire rolling as internal heat sources, while setting the convective heat dissipation coefficients of the tread and sidewall to simulate the external heat dissipation environment.

[0079] In implementation, the thermo-mechanical coupling analysis was performed using Abaqus. The tire model was defined as a "thermo-mechanical" coupled body, and material parameters (such as rubber elastic modulus and friction coefficient) were dynamically updated with temperature. This included calculations of internal heat sources and settings for heat dissipation conditions.

[0080] Internal heat source calculations include:

[0081] Frictional heat Q1: Based on the contact pressure between the tire tread and the road surface, the slip velocity, and the coefficient of friction, it is calculated according to Q1 = μ × P × v (where: μ is the coefficient of friction, P is the contact pressure, and v is the slip velocity).

[0082] Deformation heat Q2: Based on the plastic strain rate of each tire component With stress (σ), according to Calculate (where 0.9 is the mechanical work-to-heat energy conversion coefficient).

[0083] Heat dissipation settings include:

[0084] Convection cooling: The convection coefficient in the area where the tire tread contacts the air is set at 25W / m. 2 K, Sidewall setting 18W / m 2 K (refer to tire heat dissipation characteristic test data);

[0085] Ambient temperature: used to simulate normal temperature driving scenarios, preferably 25°C in this embodiment of the invention.

[0086] Furthermore, this invention incorporates frictional heat and deformation heat into the simulation through a thermo-coupling analysis mode, realistically reflecting the impact of temperature on tire material performance (such as rubber softening at high temperatures), avoiding performance misjudgments caused by neglecting temperature, setting differentiated convection heat dissipation coefficients to make the temperature field distribution more realistic, improving simulation accuracy, reducing accelerated tire wear caused by high-temperature aging, and extending service life.

[0087] In detail, the tire grip force is calculated based on the ground pressure distribution cloud map, including: calculating the longitudinal grip force and lateral grip force of the tire respectively. The longitudinal grip force is calculated based on the ground pressure distribution under braking or driving conditions, and the lateral grip force is calculated based on the ground pressure distribution under steering conditions.

[0088] In this embodiment of the invention, a braking torque (or driving torque) is applied to cause the tire to slip (slip rate 5%-20%), and a ground pressure distribution cloud map is extracted.

[0089] The longitudinal grip force is calculated as follows: the grounding area is divided into 1000 micro-units, and the longitudinal force of each micro-unit is equal to the micro-unit pressure multiplied by the corrected friction coefficient (considering the slip ratio and temperature effect). The total longitudinal grip force is the integral of the longitudinal forces of all micro-units.

[0090] The method for calculating lateral grip is as follows:

[0091] Apply a lateral load to induce a tire slip angle (2°-8°) and extract the ground pressure distribution cloud map;

[0092] The lateral slip direction at each position of the tread is determined based on the slip angle. The lateral force of each micro-unit is equal to the micro-unit pressure multiplied by the lateral friction coefficient (which increases nonlinearly with the slip angle). The total lateral grip force is the vector sum of the lateral forces of all micro-units.

[0093] Furthermore, by distinguishing between longitudinal and lateral grip, this invention specifically evaluates performance under typical operating conditions such as braking and steering, making the design more aligned with actual usage needs and reducing shortcomings caused by incomplete performance coverage. The micro-unit calculation method based on ground pressure distribution improves the accuracy of grip evaluation, avoids the errors of the overall averaging method, and provides precise guidance for structural optimization. Through the synergistic improvement of longitudinal and lateral performance, it reduces excessive wear caused by insufficient local performance (such as uneven tread wear during braking), gradually extending tire life.

[0094] Furthermore, during the mesh generation process, an adaptive densification mechanism is adopted for the first mesh density of the tire ground contact area. Specifically, this includes: firstly, dividing the basic mesh according to the initial mesh size, and then, based on the ground pressure gradient distribution pre-calculated by dynamic rolling simulation, performing secondary densification on areas where the pressure gradient exceeds the preset pressure gradient threshold. The size of the densified mesh is no greater than 50% of the size of the basic mesh, and the edge of the densified area achieves a smooth transition of mesh density through transition units.

[0095] In implementation, the initial mesh size for the grounded area is set to 10mm, and for the non-grounded area to 20mm, with initial meshing completed using Hypermesh. A short-duration dynamic rolling simulation (e.g., 1s) is performed to extract the ground pressure gradient distribution (pressure change per unit distance) in the grounded area. The preset pressure gradient threshold is determined based on actual accuracy requirements (e.g., the error rate of the 3D tire model during vehicle movement is required to be within 1%. When the ground pressure gradient is 50kPa / mm, the high gradient in the ground pressure distribution map causes significant deformation of the tire in the grounded area, resulting in an error rate greater than 1% for the 3D tire model during vehicle movement; hence, the preset pressure gradient threshold in this embodiment is 50kPa / mm). Areas exceeding the threshold (e.g., the transition area between the tire shoulder and crown) undergo secondary refinement, resulting in a mesh size ≤5mm (50% of the base size).

[0096] The boundary between the encrypted and unencrypted areas is transitioned using pyramid units (C3D6) to ensure unit quality (twist rate ≤10°, aspect ratio ≤3).

[0097] Furthermore, by setting an adaptive encryption mechanism for the grounded area, this invention can ensure the calculation accuracy in areas with severe pressure gradients, improve the accuracy of grip assessment, and provide a reliable basis for structural optimization; the simplified mesh in the non-grounded area reduces the computational load, reduces simulation time, and improves design efficiency; the transition element processing avoids stress concentration caused by abrupt changes in mesh density, ensures model convergence, reduces invalid optimization caused by simulation errors, and gradually shortens the R&D cycle by improving design efficiency.

[0098] Furthermore, the setting of contact boundary conditions includes a multi-condition contact parameter switching mechanism, specifically: corresponding friction coefficient models and contact parameters are preset for dry, wet and icy / snowy road surfaces respectively. During dynamic rolling simulation, the matching contact parameters can be automatically called according to the road surface type parameters in the load spectrum.

[0099] Furthermore, when generating typical parameter combination samples using the orthogonal experimental method, a stratified sampling strategy is adopted, specifically including: dividing the gradient range of tire sidewall width variation into several sub-intervals, selecting sample points in each sub-interval according to a preset ratio, ensuring the uniformity of sample distribution in each sub-interval, and distributing the number of sample points proportionally to the sensitivity coefficient of tire sidewall width on performance within the sub-interval, with the sensitivity coefficient determined through previous single-factor simulation experiments.

[0100] In practice, the sidewall width gradient range (180-195mm) is divided into 5 sub-ranges (180-183mm, 183-186mm, 186-189mm, 189-192mm, 192-195mm), with each sub-range having the same width (3mm).

[0101] By using single-factor simulation (changing only the sidewall width while keeping other parameters fixed), the change in grip force (ΔF) when the sidewall width changes by 1 mm in each sub-interval is calculated. The larger the ΔF, the higher the sensitivity coefficient (e.g., ΔF = 50 N / mm in the 186-189 mm interval, with a sensitivity coefficient of 1.2; ΔF = 30 N / mm in other intervals, with a coefficient of 1.0).

[0102] The total sample size is 18, and the samples are distributed according to the sensitivity coefficient: 25% (4-5 samples) of the high sensitivity interval and 18.75% (3-4 samples) of other intervals to ensure a denser sample size in sensitive areas.

[0103] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A tire design method for improving tire grip based on finite element analysis, characterized in that, include: Obtain the tire specifications of the tire to be designed and establish a parametric 3D tire model based on the tire specifications; Set the gradient range for the change in sidewall width and establish a correlation formula between sidewall width and groove depth; The parametric 3D tire model is meshed. For the ground-contact area in the parametric 3D tire model, a first mesh density is used for construction, and for the non-ground-contact area in the parametric 3D tire model, a second mesh density is used for construction, and the first mesh density is greater than the second mesh density. Obtain the constraints of the tire during vehicle movement, and superimpose the constraints on the parameterized 3D tire model; Adjust the tire sidewall width according to the aforementioned gradient range, and simultaneously adjust the groove depth according to the aforementioned correlation formula; The adjusted sidewall width and groove depth are substituted into the parametric 3D tire model to generate a new parametric 3D tire model; The tire's load spectrum is obtained, and dynamic rolling simulation is performed based on the load spectrum and the new parameterized 3D tire model to extract the ground pressure distribution cloud map. The tire grip force is calculated based on the ground pressure distribution cloud map. The response and tire grip force meet the preset requirements, and the new parameterized 3D tire model is output.

2. The tire design method for improving tire grip based on finite element analysis according to claim 1, characterized in that, The tire specifications include: tire width, aspect ratio, tire construction type, rim diameter, load index, and speed rating; The constraints include: inflation pressure loading, contact boundary conditions, and temperature boundary conditions.

3. The tire design method for improving tire grip based on finite element analysis according to claim 2, characterized in that, The correlation formula between tire sidewall width and groove depth was obtained by fitting finite element simulation data, including: Determine the independent variable, dependent variable, and constraints in the correlation formula; the independent variable is the tire sidewall width, and the dependent variable is the groove depth, the degree of groove curvature, and the sidewall inclination angle. The orthogonal experimental design method is used to set multiple gradient levels for the independent and dependent variables to filter historical data and generate a sample of typical parameter combinations covering the entire variable space. A 3D model is constructed based on the typical parameter combination sample. Finite element simulation software is used to simulate the tire driving state and extract the performance indicators during the simulation process. The performance indicators include: ground pressure uniformity, groove stress and drainage path length. Based on the importance of each performance indicator, different weights are assigned to each performance indicator. Samples of different typical parameter combinations under the same tire sidewall width are scored, and the combination of groove depth, groove curvature, and sidewall camber with the highest score is selected to form a mapping table. Curve fitting is performed on the data in the mapping table to establish the basic functions of the independent variables and each dependent variable, interaction terms are introduced to correct the parameter synergy, and the constraints are embedded. Substitute the historical data that was not involved in the fitting into the basic function to obtain the simulation results. Calculate the weighted sum of the relative errors of each dependent variable between the simulation results and the actual simulation data in the historical data, and record the weighted sum as the error. In response to the error being greater than or equal to the error threshold, supplement the samples and refit until the error is less than the error threshold.

4. The tire design method for improving tire grip based on finite element analysis according to claim 2, characterized in that, The inflation pressure loading adopts a step-by-step loading method, including: The tire is loaded with an initial pressure to eliminate the initial gap in the model; the initial pressure is a preset percentage of the target pressure. The pressure loading process between the initial pressure and the target pressure is divided into multiple loading cycles; For a single loading cycle, the tire's profile deformation is acquired in real time during the loading process. If the profile deformation is greater than or equal to a preset deformation, it is determined that there may be an anomaly in the model in the current loading step, and loading needs to be paused and the model checked. If the profile deformation is less than the preset deformation, it is determined that the model is running normally in the current loading step, and the next loading cycle can begin until the target pressure is reached.

5. The tire design method for improving tire grip based on finite element analysis according to claim 2, characterized in that, The temperature boundary conditions adopt a thermo-mechanical coupling analysis mode, taking the frictional heat and material deformation heat generated during tire rolling as internal heat sources, and setting the convective heat dissipation coefficients of the tread and sidewall to simulate the external heat dissipation environment.

6. The tire design method for improving tire grip based on finite element analysis according to claim 1, characterized in that, The calculation of tire grip force based on the ground pressure distribution cloud map includes: calculating the longitudinal grip force and lateral grip force of the tire respectively. The longitudinal grip force is calculated based on the ground pressure distribution under braking or driving conditions, and the lateral grip force is calculated based on the ground pressure distribution under steering conditions.

7. The tire design method for improving tire grip based on finite element analysis according to claim 1, characterized in that, During the mesh generation process, an adaptive densification mechanism is adopted for the first mesh density of the tire ground contact area. Specifically, this includes: firstly, dividing the basic mesh according to the initial mesh size, and then, based on the ground pressure gradient distribution pre-calculated by dynamic rolling simulation, performing secondary densification on areas where the pressure gradient exceeds a preset pressure gradient threshold. The size of the densified mesh is no greater than 50% of the size of the basic mesh, and the edges of the densified area achieve a smooth transition of mesh density through transition units.

8. The tire design method for improving tire grip based on finite element analysis according to claim 2, characterized in that, The setting of the contact boundary conditions includes a multi-condition contact parameter switching mechanism, specifically: for dry ground, wet ground and icy and snowy road surfaces, corresponding friction coefficient models and contact parameters are preset respectively. During the dynamic rolling simulation, the matching contact parameters can be automatically called according to the road surface type parameters in the load spectrum.

9. The tire design method for improving tire grip based on finite element analysis according to claim 3, characterized in that, When generating typical parameter combination samples using the orthogonal experimental method, a stratified sampling strategy is adopted, specifically including: dividing the gradient range of tire sidewall width variation into several sub-intervals, selecting sample points in each sub-interval according to a preset ratio, ensuring the uniformity of sample distribution in each sub-interval, and distributing the number of sample points proportionally to the sensitivity coefficient of tire sidewall width on performance within the sub-interval, with the sensitivity coefficient determined through previous single-factor simulation experiments.

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