Heavy-duty radial tire carcass cord compression model, analysis, and design optimization method

Abstract

The present invention relates to the technical field of tire optimization design, and specifically to a heavy-duty radial tire carcass cord compression model, analysis, and design optimization method. The present invention includes the following steps: obtaining strain distribution results, obtaining maximum compressive strain values, and comparing multiple groups of maximum compressive strain values. The present invention defines the area with negative strain distribution results as the material behavior of the carcass cord compression area, and the absolute value of the negative value is the compressive strain value of the carcass cord; the location of the maximum compressive strain value in the strain distribution result is the starting point of the bead hollowing damage; by comparing the maximum compressive strain value of the carcass cord in the strain distribution result, the design scheme with the minimum maximum compressive strain value is selected. The present invention avoids the premature damage of the heavy-duty radial tire carcass cord compression model due to bead hollowing during actual use through the optimal design scheme, saves tire trial production and testing costs, and shortens the new product development and performance improvement cycle.

Description

Technical Field

[0001] The present invention relates to the technical field of tire optimization design, and in particular to a carcass cord compression model, analysis and design optimization method for a heavy-load radial tire. Background Art

[0002] The high-turn-up design of the carcass cord of the engineering machinery radial tire under heavy load conditions makes the position from the tire rim to the sidewall in a double-layer carcass cord structure, such as Figure 3 or Figure 6 As shown. The Rubber Industry, Vol. 55, pp. 80-84, discloses a "Finite Element Analysis of Load-bearing Radial Tire Cord Force." This article establishes a finite element model of a load-bearing radial tire based on nonlinear finite element analysis software, and analyzes the basic characteristics of the cord force changes when the tire is statically loaded under standard inflation pressure and different load conditions. However, the constitutive model of the steel cord in its finite element analysis is a linear elastic model, with the same elastic modulus in tension and compression. The constitutive relationship is as follows: Figure 4 As shown in the figure. Using existing curves, it is possible to predict the range of compressive strain at the carcass turnup location. However, due to limitations in the constitutive model, it is impossible to compare the carcass cord compressive strain values between different design options, making it impossible to evaluate the performance of the design options in terms of bead hollowing. To increase the service life of radial engineering tires under heavy loads and reduce product development and testing costs, it is necessary to accurately evaluate the tire bead hollowing performance of different design options during the design phase and effectively select the optimal design. Summary of the Invention

[0003] The technical problem to be solved by the present invention is: to overcome the shortcomings of the existing technology, to provide a heavy-duty radial tire carcass cord compression model, analysis and design optimization method, which can accurately evaluate the difficulty of tire bead hollowing damage in multiple tire design schemes; to optimize the design scheme to avoid premature damage of the heavy-duty radial tire carcass cord compression model due to bead hollowing during actual use.

[0004] The first technical solution of the present invention is:

[0005] A heavy-load radial tire carcass cord compression model, comprising a rubber component, a carcass cord located within the rubber component, and other skeleton material components;

[0006] The rubber component gives the Marlow model hyperelastic properties;

[0007] Carcass cords, which give the material properties of tension and compression;

[0008] Other skeleton material components are given linear elastic isotropic material properties;

[0009] The compression model is constructed according to the tensile and compressive anisotropic material properties of the carcass cord. When the carcass cord material is subjected to compression, the elastic modulus of the compression model is 0; when the carcass cord skeleton material is subjected to tension, the elastic modulus of the compression model is positive.

[0010] Preferably, the triangular unit of the rubber component adopts a two-dimensional axisymmetric plane unit CGAX3H;

[0011] The quadrilateral element of the rubber component adopts the two-dimensional axisymmetric plane element CGAX4H;

[0012] For other skeleton material components, the one-dimensional linear axisymmetric stiffener Rebar unit SFMGAX1 is used.

[0013] The second technical solution of the present invention is:

[0014] A method for analyzing a carcass cord compression model of a heavy-load radial tire comprises the following steps:

[0015] The finite element model is subjected to implicit static simulation calculations based on the physical parameters of the heavy-duty radial tire carcass cord compression model. The boundary conditions of the heavy-duty radial tire carcass cord compression model include maximum load, inflation pressure, and tire radial load. By simulating the mechanical state of the actual tire load, an inflation pressure equivalent to that of the actual tire is applied to the inner liner surface of the engineering machinery radial tire simulation model under heavy load conditions, and a concentrated load in the tire radial direction is applied to the road reference point according to the load in actual use of the tire. By setting contact properties for the road surface and the tire tread, the tire simulation model is brought into contact with the road surface model, and the tire load is transferred to the road surface through the tread. The steps include the following:

[0016] S1: Using SYMMETRIC MODEL GENERATION technology, the 2D axisymmetric tire simulation model is converted into a 3D tire simulation model. In the circumferential direction, within the 50° closest to the road surface, a fine grid layout is used, with one grid layer generated every 1°. A coarser grid layout is used for the rest of the circumference, with one grid layer generated every 7°.

[0017] S2: Using the SYMMETRIC RESULTS TRANSFER technology, the 2D axisymmetric inflation simulation results are transferred to the 3D tire simulation model, and radial loads are applied to the tire simulation model based on the inflation simulation results.

[0018] S3: Abaqus finite element analysis software is used to perform three-dimensional tire loading simulation analysis.

[0019] The third technical solution of the present invention is:

[0020] A method for optimizing the design of a heavy-load radial tire carcass cord compression model comprises the following steps:

[0021] Step 1: Obtaining strain distribution results: This includes the following steps:

[0022] S11: Convert the heavy-duty radial tire carcass cord compression model into a finite element model by specifying element types and assigning material properties;

[0023] S12: Simulating and analyzing the finite element model to obtain tire three-dimensional loading simulation analysis results;

[0024] S13: extracting the strain distribution results in the carcass cord length direction from the tire three-dimensional loading simulation analysis results;

[0025] Step 2: Obtaining the maximum compressive strain value: This includes the following steps:

[0026] The area with negative strain distribution results is defined as the material behavior of the carcass cord in the compression area. The absolute value of the negative value is the compressive strain value of the carcass cord. The location of the maximum compressive strain value in the strain distribution result is the starting point of the bead hollowing damage. The size of the compressive strain value is used to evaluate the difficulty of tire bead hollowing damage.

[0027] Step 3: Comparison of multiple groups of maximum compressive strain values: This includes the following steps:

[0028] Repeat steps 1 and 2 to obtain the strain distribution results of multiple tire design schemes. By comparing the maximum compressive strain values of the carcass cords in the strain distribution results, select the design scheme with the smallest maximum compressive strain value, which is the design scheme least likely to cause bead hollowing damage.

[0029] Preferably, in step S13 of step 1, the strains LE11 of all carcass Rebar units in the tire three-dimensional loading simulation analysis results are extracted and displayed using a distribution cloud diagram.

[0030] Preferably, in step 2, the indicator of tire bead hollowing damage is the compressive strain of the carcass cord Rebar unit, which physically means the compressive deformation per unit length of the carcass cord under load, and the method for extracting the compressive strain of the carcass cord Rebar unit.

[0031] Preferably, in the step 2, the calculation results of the tire simulation model are displayed so that only other skeleton material components are displayed, and the calculation results of the compressive strain in the length direction of all other skeleton material components are displayed. A positive compressive strain value in the result indicates that the carcass cord is stretched, and its absolute value is the tensile strain value; a negative compressive strain value in the result indicates that the carcass cord is compressed, and its absolute value is the compressive strain value. The tire rim hollow damage index is the maximum compressive strain value of the carcass cord.

[0032] Preferably, in the step 2, the material behavior of the compressed area in the Rebar unit LE11 of the carcass cord is the negative area of the carcass cord after loading, and the maximum absolute value in the negative area is the maximum compressive strain value of the carcass cord; the greater the compressive strain of the carcass cord, the greater the possibility of hollowing of the tire bead, and the corresponding tire will suffer from hollowing damage sooner.

[0033] Preferably, in step three, the design scheme with the smallest maximum compressive strain value is selected to guide the design of the carcass cord compression model of the heavy-duty radial tire, and the product is optimized during the design stage to assist in improving the durability of the tire rim.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] The simulation analysis method and evaluation indicators proposed in the present invention accurately evaluate the hollowing performance of the tire bead, are highly consistent with the actual market performance of the product, and effectively support the improvement of the durability performance of the bead of the carcass cord compression model of heavy-load radial tires, saving tire trial production and testing costs and shortening the new product development and performance improvement cycle.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] The simulation analysis method and evaluation indicators proposed in the present invention accurately evaluate the hollowing performance of the tire bead, are highly consistent with the actual market performance of the product, and effectively support the improvement of the durability performance of the bead of the carcass cord compression model of heavy-load radial tires, saving tire trial production and testing costs and shortening the new product development and performance improvement cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0039] Figure 1 3 is a carcass cord compression model diagram of the carcass cord in Example 1.

[0040] Figure 2 This is a circumferential grid layout diagram of the three-dimensional tire simulation model in Example 1.

[0041] Figure 3 This is a structural design diagram of an engineering machinery radial tire under heavy load conditions in Example 1.

[0042] Figure 4 It is a carcass cord compression model diagram of the carcass cord in the prior art.

[0043] Figure 5 This is a circumferential grid layout diagram of the three-dimensional tire simulation model in Example 2.

[0044] Figure 6 This is a structural design diagram of an engineering machinery radial tire under heavy load conditions in Example 2.

[0045] Figure 7 2D finite element mesh diagram of the carcass cord in Example 1.

[0046] Figure 8 This is the distribution cloud diagram of the tire simulation model in Example 1.

[0047] In the figure: 1. Carcass cord; 2. Contact area; 3. Maximum compressive strain value; 4. Material behavior in the compression area. DETAILED DESCRIPTION

[0048] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only 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 making creative efforts should fall within the scope of protection of the present invention.

[0049] Example 1

[0050] like Figure 1 As shown, this embodiment simulates and analyzes the bead hollowing damage performance under the conditions of a carcass cord compression model of 27.00R49 and an inflation pressure of 700KPa and a tire load of 40 tons, including the following steps:

[0051] Step 1: Obtaining strain distribution results.

[0052] S11: For the structural design of the 27.00R49 engineering machinery radial tire, the first design scheme (such as Figure 3 ), divide the two-dimensional finite element mesh (such as Figure 7 ). Figure 1 Also shown is the mesh model of the carcass cord 1. Different rubber components and other skeleton material components in the divided finite element model are assigned corresponding material properties.

[0053] Specify the element type for the 2D axisymmetric mesh model of the tire. For the triangular elements of the rubber components in the tire simulation model, use the 2D axisymmetric plane element CGAX3H; for the quadrilateral elements of the rubber components in the tire simulation model, use the 2D axisymmetric plane element CGAX4H; for other skeleton material components in the tire simulation model, use the 1D linear axisymmetric Rebar element SFMGAX1.

[0054] Assign material properties to the tire's two-dimensional axisymmetric mesh model. The rubber element is assigned the Marlow model hyperelastic property; the other skeleton materials except the carcass cord 1 are assigned the linear elastic isotropic material property; the carcass cord 1 is assigned the following Figure 1 The tensile and compressive properties of the carcass cord 1 of the present invention are used to construct a compression model (such as Figure 1 ) and the existing technology of constructing compression model with different tensile and compressive material properties (such as Figure 4 ), which differs in the negative strain region. In this example, the carcass cord structure is "7×7×0.25+0.15HT." During tire simulation, when the carcass cord 1 material is subjected to tensile force, the elastic modulus of the compression model is 160 GPa. When the carcass cord 1 material is subjected to compressive force, the elastic modulus of the compression model is 0.

[0055] S12: Perform two-dimensional assembly, inflation, and three-dimensional loading calculations on the finite element model of the engineering machinery radial tire under heavy load conditions in S1.

[0056] S121: Based on the maximum load expected in commercial use, the tire model's inflation pressure was set to 700 kPa, and the radial load was set to 40 tons. Abaqus finite element analysis software was used for implicit statics simulation.

[0057] S122: Using SYMMETRIC MODEL GENERATION technology, the two-dimensional axisymmetric tire simulation model is converted into a three-dimensional tire simulation model. In the circumferential direction, a fine grid layout is used with one grid layer generated every 1° within the 50° range closest to the road surface; a coarser grid layout is used with one grid layer generated every 7° at other locations in the circumferential direction. This is to balance the accuracy of the tire simulation model's loading simulation calculation results near contact area 2 with the simulation calculation efficiency of the entire model. The circumferential grid layout of the three-dimensional tire simulation model is as follows: Figure 2 As shown, Figure 2 The circumferential mesh refinement area is also shown.

[0058] S123: Using the SYMMETRIC RESULTS TRANSFER technology, the 2D axisymmetric inflation simulation results are transferred to the 3D tire simulation model. Based on the inflation simulation results, a 40-ton radial load is applied to the tire simulation model.

[0059] S13: After the calculation is completed, the strain LE11 of all carcass Rebar units in the tire simulation model calculation results is extracted and displayed in the form of a distribution cloud diagram, such as Figure 2 shown.

[0060] Step 2: Obtain the maximum compressive strain value.

[0061] In the tire simulation model carcass Rebar unit LE11 in S13, the area less than 0 is the material behavior 4 of the compression area of the carcass cord 1 after loading. In the calculation results of this example, the minimum value of the material behavior 4 of the compression area is -0.07162, as shown in Figure 2 As shown, its absolute value is 0.07162, which represents the maximum compressive strain value 3 of carcass cord 1, calculated from the load calculation results of this tire simulation model. Expressed as a percentage, it is 7.162%. The maximum compressive strain value 3 of carcass cord 1 is an indicator for evaluating tire bead hollowing damage resistance. This value physically represents the maximum compressive deformation per unit length of carcass cord 1 at the turnup position after the tire is loaded. The larger this value in the tire design, the more susceptible the tire will be to bead hollowing damage during actual use.

[0062] Step 3: Comparison of multiple groups of maximum compressive strain values.

[0063] Repeat steps 1 and 2 for multiple sets of tire design schemes to obtain the maximum compressive strain value 3 of the carcass cord 1 in all design schemes. Rank the maximum compressive strain values 3 calculated for all design schemes participating in the comparative analysis. The preferred scheme is the one with the smallest maximum compressive strain value 3 of the carcass cord 1 among all design schemes.

[0064] The finite element analysis method for tire rim hollowing damage performance proposed in the present invention accurately predicts the actual market performance of the product, can effectively guide the structural design of engineering machinery radial tires under heavy load conditions, and optimize products during the design stage to assist in improving the durability performance of the tire rim.

[0065] Example 2

[0066] To optimize the design solution, how to use the comparison of multiple groups of maximum compressive strain values is explained. The principle is explained below in conjunction with specific embodiments.

[0067] Assume that Figure 3 The first scheme shown is to design the structure of the engineering machinery radial tire with specification 27.00R49. Figure 2 The cord compressive strain value was given as 7.162%.

[0068] Assume that Figure 6 The second solution shown is to design an engineering machinery radial tire of the same specification 27.00R49, and perform steps 1 to 2 to obtain Figure 5 The cord compressive strain value was given as 8.519%.

[0069] It should be noted that Figure 6 The circled part is the Figure 1 The main difference is that the distribution cloud diagram of the tire simulation model can be distinguished by numerical values.

[0070] Compared with the cord compressive strain value of 7.162% in the first solution in Example 1, the cord compressive strain of 8.519% in the second solution is greater than 7.162%. Therefore, it can be concluded that the loop performance of the first solution is better than that of the second solution. Of the two solutions, the first solution is the preferred solution.

[0071] Example 3

[0072] The above-mentioned embodiment 1, embodiment 2 and the accompanying drawings do not limit the product form and style of the present invention. There are other details that can be refined, which are explained here.

[0073] For example, the arrangement scheme of the tire three-dimensional finite element mesh in the circumferential direction in step 1 can be a scheme of refining any contact patch 2, or a refined three-dimensional mesh in the entire circumferential direction without considering the computational cost.

[0074] For example, the carcass frame material tensile-compressive anisotropic constitutive model in step 1 can be a constitutive model of the mechanical behavior of other materials that exhibit a lower compression modulus than the tensile modulus of the carcass cord. The tire model in this embodiment is not limited to the 27.00R49 specification; it can be any radial engineering tire with a high-turnup carcass structure. Any appropriate changes or modifications made by persons of ordinary skill in the art should be considered within the scope of this invention.

[0075] In summary, the present invention discloses a finite element analysis method for evaluating the tire rim hollowing damage performance, which aims to evaluate the tire rim hollowing damage performance among multiple design schemes, accurately select the preferred design scheme, and avoid the heavy-load radial tire carcass cord compression model from being damaged and destroyed prematurely due to rim hollowing during the design stage. Through mechanical analysis and the market performance of the product, it was determined that the mechanical reason for the rim hollowing of the heavy-load radial tire carcass cord compression model is that the carcass cord of the high-turn-up tire is compressed and deformed under heavy load. On this theoretical basis, the maximum compressive strain value 3 of the carcass cord 1 of the engineering machinery radial tire simulation model under heavy load conditions is calculated by the finite element simulation analysis method, and the design scheme with the smallest maximum compressive strain value of the carcass cord 1 at the dangerous point among the multiple design schemes is selected, so as to avoid the tire product from being damaged prematurely in actual use from the design stage.

Claims

1. A design optimization method for a heavy-duty radial tire carcass cord compression model, using a heavy-duty radial tire carcass cord compression model, wherein the heavy-duty radial tire carcass cord compression model includes a rubber component, a carcass cord (1) located in the rubber component, and other skeleton material components; the rubber component is endowed with Marlow model hyperelastic properties; the carcass cord (1) is endowed with tension and compression anisotropic material properties; Other skeleton material components are endowed with linear elastic isotropic material properties; a compression model is constructed based on the tensile and compressive anisotropic material properties of the carcass cord (1); when the carcass cord (1) material is subjected to a compressive force, the elastic modulus of the compression model is 0; when the carcass cord (1) skeleton material is subjected to a tensile force, the elastic modulus of the compression model is a positive value, characterized in that: The steps include: Step 1: Obtaining strain distribution results: This includes the following steps: S11: Convert the heavy-duty radial tire carcass cord compression model into a finite element model by specifying element types and assigning material properties; S12: Simulate and analyze the finite element model to obtain tire three-dimensional loading simulation analysis results; S13: extracting the strain distribution results of the carcass cord (1) in the length direction from the tire three-dimensional loading simulation analysis results; Step 2: Obtaining the maximum compressive strain value: This includes the following steps: The area with negative strain distribution results is defined as the material behavior (4) of the compression area of the carcass cord (1), and the absolute value of the negative value is the compressive strain value of the carcass cord (1); the position of the maximum compressive strain value (3) in the strain distribution results is the starting point of the bead hollowing damage, and the difficulty of the tire bead hollowing damage is evaluated by the size of the compressive strain value; The indicator of tire bead hollowing damage is the compressive strain of the carcass cord (1) Rebar unit, and its physical meaning is the compressive deformation per unit length of the carcass cord (1) under load. The method for extracting the compressive strain of the carcass cord (1) Rebar unit; The calculation results of the tire simulation model are displayed so that only other skeleton material components are displayed, and the calculation results of the compressive strain in the length direction of all other skeleton material components are displayed. A positive compressive strain value in the result indicates that the carcass cord (1) is stretched, and its absolute value is the tensile strain value; a negative compressive strain value in the result indicates that the carcass cord (1) is compressed, and its absolute value is the compressive strain value. The tire bead hollowing damage index is the maximum compressive strain value (3) of the carcass cord; The material behavior (4) of the compression area in the Rebar unit LE11 of the carcass cord (1) is a negative area of the carcass cord (1) after loading, and the maximum absolute value in the negative area is the maximum compressive strain value (3) of the carcass cord (1); the greater the compressive strain of the carcass cord (1), the greater the possibility of hollowing of the tire bead, and the earlier the tire will suffer hollowing damage. Step 3: Comparison of multiple groups of maximum compressive strain values: This includes the following steps: Repeat steps 1 and 2 to obtain strain distribution results of multiple tire design schemes. By comparing the maximum compressive strain value (3) of the carcass cord (1) in the strain distribution results, the design scheme with the smallest maximum compressive strain value (3) is selected, which is the design scheme that is least likely to cause bead hollowing damage.

2. The design optimization method for the heavy-load radial tire carcass cord compression model according to claim 1, characterized in that: In step S13 of step 1, the strain LE11 of all carcass Rebar units in the tire three-dimensional loading simulation analysis results is extracted and displayed using a distribution cloud diagram.

3. The design optimization method for the carcass cord compression model of a heavy-duty radial tire according to claim 1, characterized in that: In the step 3, the design scheme with the smallest maximum compressive strain value (3) is selected to guide the design of the carcass cord compression model of the heavy-duty radial tire, and the product is optimized in the design stage to assist in improving the durability performance of the tire rim.

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