A detailed analysis method, device and procedure for the contribution of tire deformation modes to rolling resistance

Abstract

The present invention relates to the technical field of intelligent computer design of tires, and more particularly to a method, apparatus, and computer program for refining the analysis of the contribution of tire deformation modes to rolling resistance. The method comprises the following steps: 1) establishing a tire finite element model and performing load analysis; 2) extracting the true stress and strain values of elements at the same position and different angles around the tire, and fitting the values of σ and ε using a 100th-order trigonometric series; 3) using the fitted parameter data to calculate the energy loss density e of the rubber material element under the corresponding deformation mode; and 4) using a program to plot a tire cross-section element mesh diagram based on the node coordinates and element composition, filling the elements with different colors based on the energy loss density value of each element under a single deformation mode. The present invention accurately locates areas that contribute significantly to rolling resistance and determines the contribution of each tire deformation mode to rolling resistance, thereby refining the analysis of tire rolling resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of computer intelligent design of tires, and in particular to a method, device and computer program for detailed analysis of the contribution of tire deformation modes to rolling resistance. Background Art

[0002] With the implementation of European tire labeling regulations, the industry trend toward green tires, and the demand for electric vehicle range, low rolling resistance tires have long become a common pursuit in the tire industry. Rolling resistance is a key indicator of tire performance; tires that fail to meet standards are unsaleable. Factors affecting tire rolling resistance primarily include materials, structure, road conditions, and operating conditions. Road conditions and operating conditions are uncontrollable factors, but for tire design engineers, structure and materials are the two primary approaches to controlling tire rolling resistance. Testing and finite element simulation are the main methods for measuring and evaluating tire rolling resistance. While testing methods can accurately obtain rolling resistance values, they require tire production and testing, which is costly and time-consuming. Furthermore, they fail to capture internal tire deformation, requiring multiple tests on tires with different structures to identify the cause of high or low rolling resistance. In contrast, finite element simulation methods offer lower costs, shorter cycle times, and intuitive visualization of tire deformation and stress, facilitating analysis of the impact of structure and materials on tire deformation and rolling resistance. Current simulation analysis of tire rolling resistance primarily focuses on the contribution of individual tire components to its overall rolling resistance, as well as the prediction of rolling resistance after adjusting the tire structure or materials. However, this provides limited guidance to tire design engineers and cannot precisely locate specific locations where the tire's rolling resistance is greatest. For example, the tire tread structure covers the entire running surface of the tire. Currently, only the contribution of the entire tread to rolling resistance can be analyzed, but it is impossible to determine which part of the tread (the center or the edge) contributes the most.

[0003] At the same time, the stress state of the rubber material in the tire is very complex. According to traditional mechanical analysis, it contains six strain (stress) components. The current rolling resistance analysis method cannot determine the contribution of various deformation modes to the rolling resistance of various parts of the tire, and thus cannot guide material testing (calculating rolling resistance generally requires testing the loss tangent value of the rubber material, and the loss tangent value is related to the deformation mode (tension or shear)). It is necessary to obtain the main deformation mode that contributes more to the rolling resistance of each part and test the material performance based on the deformation mode. This has a very important guiding role for tire material design engineers. Summary of the Invention

[0004] The purpose of the present invention is to solve the problems existing in the above-mentioned prior art, namely, the current simulation analysis research on tire rolling resistance mainly focuses on the contribution of each tire component to its overall rolling resistance, and the rolling resistance prediction after adjusting the tire structure or material. However, this has limited guiding role for tire design engineers and cannot accurately locate the specific location where the tire rolling resistance is large. For example, the tire tread structure covers the entire tire driving surface. Currently, only the rolling resistance contribution of the entire tread can be analyzed, and it is impossible to determine which part of the tread (the center of the tread or the edge of the tread) contributes more. At the same time, the stress state of the rubber material in the tire is very complex. According to traditional mechanical analysis, it contains six strain (stress) components. The current rolling resistance analysis method cannot determine the contribution of various deformation modes to the rolling resistance of various parts of the tire, and thus cannot guide material testing (calculating rolling resistance generally requires testing the loss tangent value of the rubber material, and the loss tangent value is related to the deformation mode (tensile or shear)).

[0005] Furthermore, a detailed analysis method of the contribution of tire deformation patterns to rolling resistance is provided, which enables accurate positioning of the parts that contribute most to rolling resistance and obtains the contribution of the deformation patterns of various parts of the tire to rolling resistance, thereby refining the analysis of tire rolling resistance.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

[0007] A detailed analysis method for the contribution of tire deformation modes to rolling resistance includes the following steps:

[0008] 1) Establish a tire finite element model and perform load analysis: Mesh the tire design drawings (material distribution diagrams), assign material properties, apply rated inflation pressure, and perform inflation analysis. Based on the inflation analysis, apply the rated load to the tire and perform tire load analysis, outputting the stress and strain values of all rubber material elements.

[0009] 2) Use the program to extract the true stress and strain values of the unit at the same position and different angles around the tire, record them as σ and ε respectively, take the angle as the x value, and x in radians, and use the 100th order trigonometric series to fit the σ and ε values:

[0010]

[0011]

[0012] 3) Use the fitted parameter data to calculate the energy loss density e of the rubber material unit under the corresponding deformation mode. The tanδ value is the loss tangent of the rubber material.

[0013]

[0014] 4) Use the program to draw a tire cross-section unit mesh diagram based on the node coordinates and unit composition. The units are closed triangles or quadrilaterals. Use the program to fill the units with different colors based on the energy loss density values of each unit under a single deformation mode calculated in the third step.

[0015] Preferably, in step 1), the tire material distribution map is meshed into triangular or quadrilateral units, the skeleton material is meshed into 2-node one-dimensional units, and material properties are assigned to each component material to establish a tire finite element model.

[0016] Preferably, in step 1), an air pressure of 0.25 MPa is applied to the inner surface of the tire inner liner, and inflation analysis is performed using Abaqus software.

[0017] Preferably, in step 1), based on the two-dimensional inflation analysis, the tire section is rotated 360 degrees and the section is divided circumferentially, with one circumference divided into 110 sections. The tire rim is fixed, a load of 5881N is applied to the road surface, the road surface is moved toward the rim, a load analysis is performed, and the stress and strain values of all rubber material units are output.

[0018] Preferably, in step 2), a program is written in Python to extract the true stress and strain values of the units at the same position and different angles around the tire.

[0019] Preferably, the stress and strain values in step 2) include the following: Figure 5 Shown are direction 11, direction 22, direction 33, direction 12 or direction 21, direction 13 or direction 31, and direction 23 or direction 32.

[0020] Preferably, the step 4) uses the matplotlib program in Python to draw a tire cross-section unit grid diagram according to the node coordinates and unit composition.

[0021] Furthermore, the present invention also discloses a computer device, including a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method described in any one of the above technical solutions.

[0022] Furthermore, the present invention also discloses a computer-readable storage medium on which a computer program or instruction is stored. When the computer program or instruction is executed by a processor, the steps of the method described in any one of the above technical solutions are implemented.

[0023] A computer program product includes a computer program or instructions, which, when executed by a processor, implements the steps of the method described in any one of the above technical solutions.

[0024] By adopting the above technical solution, the present invention can achieve accurate positioning of the parts that contribute more to the rolling resistance and obtain the contribution of the deformation mode of each part of the tire to the rolling resistance, thereby refining the analysis of the tire rolling resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is the material distribution map of the 21550R15 tire;

[0026] Figure 2 21550R15 tire section mesh and material components;

[0027] Figure 3 The deformation result of 21550R15 tire inflation;

[0028] Figure 4 The three-dimensional circumferential mesh division result of the 21550R15 tire;

[0029] Figure 5 The three-dimensional load results and direction identification of the 21550R15 tire;

[0030] Figure 6 This is the strain output after load analysis for the 21550R15 tire;

[0031] Figure 7 is the 11-direction stress of unit 3 in the 21550R15 tire within one week;

[0032] Figure 8 The 11-directional strain of unit 3 in a 21550R15 tire within one week;

[0033] Figure 9 This is the trigonometric series fitting result of the 11-direction strain of unit 3 in the 21550R15 tire within one week;

[0034] Figure 10 The rolling resistance distribution of a 21550R15 tire caused by deformation in 11 directions;

[0035] Figure 11 The rolling resistance distribution of a 21550R15 tire caused by deformation in 22 directions;

[0036] Figure 12 The rolling resistance distribution of a 21550R15 tire caused by deformation in 33 directions;

[0037] Figure 13 The rolling resistance distribution of a 21550R15 tire caused by deformation in 12 directions;

[0038] Figure 14 The rolling resistance distribution of a 21550R15 tire caused by deformation in 13 directions;

[0039] Figure 15 Rolling resistance distribution of a 21550R15 tire caused by deformation in 23 directions. DETAILED DESCRIPTION

[0040] The present invention will be further described in detail below with reference to the accompanying drawings: This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation method is given, but the protection scope of the present invention is not limited to the following embodiments.

[0041] Take 21550R15 tire as an example:

[0042] The first step is to analyze the tire material distribution map ( Figure 1 ) to divide the mesh into triangular or quadrilateral elements ( Figure 2 ), the skeleton material is divided into 2-node one-dimensional units, and the material properties of each component are assigned (Table 1) to establish a tire finite element model. A 0.25MPa air pressure is applied to the inner surface of the tire inner liner, and the inflation analysis is performed using Abaqus software. The results are as follows Figure 3 As shown. Based on the two-dimensional inflation analysis, the tire section is rotated 360 degrees and divided into sections in the circumferential direction, with one circle being divided into 110 sections ( Figure 4 ), fix the tire rim, apply a load of 5881N to the road surface, move the road surface toward the rim, and perform load analysis ( Figure 5 ) and output the stress and strain values of all rubber material elements ( Figure 6 ).

[0043] The second step is to use Python to write a program to extract the true stress and strain values of the unit at the same position and different angles around the tire (including 11 directions, 22 directions, 33 directions, 12 directions (equal to 21 directions), 13 directions or 31 directions and 23 directions or 32 directions, such as Figure 5 As shown) are recorded as σ value (stress) and ε value (strain), and the angle is x value (x is in radians), and the relationship curve between x and σ and ε is plotted ( Figure 7 and Figure 8 ), use the 100th order trigonometric series to fit the σ and ε values:

[0044]

[0045]

[0046] The first 10 order parameters of the strain fitting of unit 3 in 11 directions are shown in Table 2.

[0047] Step 3: For each deformation mode unit data, use the 100 σ obtained after fitting nc Parameters, 100 εns Parameters, 100 ε nc Parameters and 100 ε ns The energy loss density e of the rubber material unit under the corresponding deformation mode is calculated by parameters. The tanδ value is the loss tangent of the corresponding unit rubber material (as shown in Table 1).

[0048]

[0049] Some of the calculation results are shown in Table 3.

[0050] Table 1 Material properties of various components of the 21550R15 tire

[0051]

[0052]

[0053] Table 2 shows the fitting coefficients of some trigonometric series for the circumferential strains in the 11 directions of unit 3 of the 21550R15 tire.

[0054] Order <![CDATA[ε nc ]]> <![CDATA[ε ns ]]> n＝1 0.048677128161277006 -0.01178 n＝2 0.005762 0.034562 n＝3 -0.02496 0.006944 n＝4 -0.01306 -0.01652 n＝5 0.010247 -0.0155 n＝6 0.009846 0.008189 n＝7 -0.00664 0.005613 n＝8 -0.00468 -0.00443 n＝9 0.00364 -0.00312 n＝10 0.000865 0.003969

[0055] Table 3 shows the rolling loss values generated by the six deformation modes of some units of the 21550R15 tire.

[0056]

[0057]

[0058] Step 4: Use the Python matplotlib program to draw the tire cross-section unit grid diagram based on the node coordinates and unit composition. The unit is a closed triangle or quadrilateral. Use the program to fill the unit with different colors according to the energy loss density value of each unit in a single deformation mode calculated in the third step. The result is as follows: Figure 11-Figure 15 .

[0059] The detailed analysis of tire rolling resistance achieved by the above technology can intuitively obtain the main causes of rolling resistance in different parts of the tire, such as Figure 13 It can be seen that the rolling resistance of the bead and sidewall caused by the 33 direction is very small, that is, there will be basically no large-scale deformation in the 33 direction. The direction of reducing the rolling resistance of the bead area is to reduce the shear deformation in the 13 direction ( Figure 14 ),pass Figure 14Comparing this with the other five results, it can be seen that the primary cause of rolling resistance in the sidewall region is shear deformation in the 13-direction. Therefore, the shear mode should be used when measuring the tanδ value of the sidewall rubber material. This brief analysis demonstrates that this patented technology can rapidly and cost-effectively analyze tire rolling resistance in detail, significantly improving product development efficiency and refining product structural design.

[0060] The foregoing are merely preferred embodiments of the present invention. These embodiments are all different implementations based on the overall concept of the present invention. The scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A detailed analysis method of the contribution of tire deformation mode to rolling resistance, characterized in that The method comprises the following steps: 1) Establish a tire finite element model and perform load analysis: Mesh the tire design drawings, assign material properties, apply rated inflation pressure, and perform inflation analysis. Based on the inflation analysis, apply the rated load to the tire and perform tire load analysis, outputting the stress and strain values of all rubber material elements. 2) Use the program to extract the true stress and strain values of the unit at the same position and different angles around the tire, record them as σ and ε respectively, take the angle as the x value, and x in radians, and use the 100th order trigonometric series to fit the σ and ε values: 3) Use the fitted parameter data to calculate the energy loss density e of the rubber material unit under the corresponding deformation mode. The tanδ value is the loss tangent of the rubber material. 4) Use the program to draw a tire cross-section unit mesh diagram based on the node coordinates and unit composition. The units are closed triangles or quadrilaterals. Use the program to fill the units with different colors based on the energy loss density values of each unit under a single deformation mode calculated in step 3).

2. The method for refining the contribution of tire deformation mode to rolling resistance according to claim 1, characterized in that: Step 1) Mesh the tire material distribution map into triangular or quadrilateral elements, divide the skeleton material into two-node one-dimensional elements, and assign material properties to each component material to establish a tire finite element model.

3. The method for refining the contribution of tire deformation mode to rolling resistance according to claim 1, characterized in that: Step 1) Apply 0.25 MPa air pressure to the inner surface of the tire inner liner and perform inflation analysis using Abaqus software.

4. The method for refining the contribution of tire deformation mode to rolling resistance according to claim 1, characterized in that: Step 1) Based on the 2D inflation analysis, rotate the tire section 360 degrees and divide it circumferentially, dividing the tire into 110 sections. With the tire rim fixed, apply a 5881N load to the road surface, causing the road surface to move toward the rim. Perform a load analysis and output the stress and strain values for all rubber material elements.

5. The method for refining the contribution of tire deformation mode to rolling resistance according to claim 1, characterized in that: Step 2) Use Python to write a program to extract the true stress and strain values of the elements at the same position and different angles around the tire.

6. The method for refining the contribution of tire deformation mode to rolling resistance according to claim 1, characterized in that: Step 4) Use the matplotlib program in Python to draw the tire cross-section unit grid diagram based on the node coordinates and unit composition.

7. A computer device comprising a memory, a processor, and a computer program stored in the memory, characterized in that: The processor executes the computer program to implement the steps of the method according to any one of claims 1 to 6.

8. A computer-readable storage medium having a computer program or instruction stored thereon, characterized in that: When the computer program or instruction is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

9. A computer program product comprising a computer program or instructions, characterized in that When the computer program or instruction is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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