Method for improving simulation calculation precision of engineering tire weight

Abstract

The application discloses a method for improving the simulation calculation precision of the weight of an engineering tire and relates to the technical field of tires. The application improves the calculation precision of the volume of a steel cord by optimizing the sectional area of the steel cord of the engineering tire, corrects the weight error of the engineering tire caused by the excessive rubber material in the finite element simulation model of the engineering tire by optimizing the density of the steel cord, and accurately corrects the problem of insufficient precision of the simulation result of the weight of the simulation model of the engineering tire caused by the defects of the rebar model.

Description

Technical Field

[0001] This invention relates to the field of tire technology, and more specifically to a method for improving the accuracy of simulation calculations of engineering tire weight. Background Technology

[0002] The weight calculation result of the tire simulation model is an important part of the finite element simulation analysis of engineering tires. Current tire finite element simulation analysis technology uses rebar elements to simulate steel cord material components and rubber elements to simulate rubber material components. The simulation result of tire weight is the sum of the total weight of the rebar elements and the total weight of the rubber elements in the simulation model. The weight of the rebar element is calculated by defining the rebar's cross-sectional area parameters and density; the weight of the rubber element is calculated by using the area reflected in the tire material distribution map and the density of the rubber material. Accurately defining the rebar cross-sectional area and density is a necessary condition for obtaining accurate simulation results of the engineering tire weight.

[0003] Tire steel cord is an assembly of steel wires formed by twisting multiple straight, standard cylindrical steel wires together. Before twisting, each individual steel wire is straight, and after twisting, it becomes spiral. In existing technology, the cross-sectional area of ​​the rebar unit of a steel cord composed of multiple steel wires is calculated as the sum of the circular cross-sectional areas of all the steel wires constituting the cord. The density of the rebar unit is set as the bulk density of a single steel wire in the cord, typically the density of steel (7.8 × 10⁻⁶). -3 g / mm 3 Define the cross-sectional area and density of the rebar elements in the tire finite element model calculation file, submit the calculation, and you can read the tire weight simulation results.

[0004] However, this simulation calculation method has the following problems:

[0005] (1) Steel cord is made of multiple thin single steel wires twisted together. The actual shape of the steel wire in the steel cord is a spiral metal wire. The cross-sectional shape of a single steel wire on the cross-section of the steel cord is elliptical. The cross-sectional area of ​​the rebar unit of the steel cord is calculated by summing the cross-sectional areas of the single steel wires. This does not match the actual cross-sectional area value of the steel cord, resulting in a deviation between the tire weight simulation results and the actual results.

[0006] (2) The steel cords in a tire have a solid volume, and there is no rubber material in the space where the steel cords are located, such as... Figure 1 As shown in the tire finite element simulation model, the rebar element cross-section is defined by mathematical parameters. The steel cord rebar element is geometrically represented as a spatial membrane. The steel cord accounts for 0% of the geometric volume in the tire simulation model. Rubber elements still exist in the geometric space where the steel cord is located, such as... Figure 2As shown, the extra geometric volume of rubber compared to the actual tire is included in the simulation calculation of tire weight. Therefore, the tire weight calculated using current technology is higher than the actual value.

[0007] In summary, there is an urgent need to improve the finite element simulation calculation method for tire weight in order to enhance the accuracy of finite element simulation in predicting tire weight. Summary of the Invention

[0008] The technical problem to be solved by this invention is to overcome the shortcomings of the prior art, accurately identify the defects of the rebar unit in weight calculation, and provide a simple, feasible and effective method to improve the accuracy of engineering tire weight simulation calculation.

[0009] The technical solution of this invention is as follows:

[0010] The method to improve the accuracy of engineering tire weight simulation calculation includes the following steps:

[0011] S1 optimizes the calculation method for the cross-sectional area of ​​steel cord, calculating the cross-sectional area of ​​the steel cord using its volumetric density and linear density:

[0012] S1-1: Obtain the weight per unit volume of the steel cord, i.e., the bulk density ρ1 of the steel cord;

[0013] S1-2: Obtain the weight per unit length of steel cord through actual measurement, i.e., the linear density ρ2 of steel cord;

[0014] S1-3: The cross-sectional area of ​​the steel cord is calculated as A = ρ2 / ρ1;

[0015] The calculation method for the density of S2 steel cord involves adjusting the material density of the steel cord to remove excess rubber material mass from the geometrically located area of ​​the steel cord.

[0016] S2-1: Obtain the weight per unit volume of the rubber material that is bonded to the steel cord, i.e., the bulk density ρ3 of the rubber material;

[0017] S2-2: Calculate the linear density of steel cord ρ = ρ1 - ρ3;

[0018] S3 Tire Simulation Calculation of Steel Cord Rebar Element Parameters: Define the cross-sectional area A of the steel cord obtained in step S1 as the cross-sectional area of ​​the steel cord rebar element, and define the steel cord density ρ calculated in step S2 as the density of the steel cord. Perform tire finite element simulation calculation, and read the tire weight simulation analysis results after the simulation calculation is completed.

[0019] Preferably, the bulk density of the steel cord is usually a constant, i.e., ρ1 = 7.8 × 10⁻⁶. -3 g / mm 3 .

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] This invention improves the accuracy of steel cord volume calculation by optimizing the cross-sectional area of ​​the steel cord in engineering tires. It also corrects the weight error caused by excess rubber material in the finite element simulation model of engineering tires by optimizing the steel cord density, accurately addressing the insufficient accuracy of weight simulation results due to defects in the Rebar model. The method of this invention is clear in principle, simple in calculation, and has significant effects, possessing important engineering value for improving the reliability of tire simulation results. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the geometric relationship between steel cords and rubber in a tire, where the shaded area represents the steel cords and the remaining blank areas represent the rubber.

[0023] Figure 2 This is a schematic diagram of the geometric relationship between rebar elements and rubber elements in the simulation model, where the blue part represents rebar elements and the remaining blank part represents rubber elements.

[0024] Figure 3 This is a schematic diagram of the material design distribution for a 460 / 95R25 tire.

[0025] Figure 4 This is a schematic diagram of the material design distribution for a 12.00R24 tire.

[0026] Figure 5 This is a schematic diagram of the material design distribution for a 35 / 65R33 tire.

[0027] Figures 3-5 In the middle, 1. Rubber material components; 2. Steel cord components. Detailed Implementation

[0028] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of this invention will be clearly and completely described below in conjunction with the embodiments of this invention.

[0029] Example 1

[0030] This embodiment uses a 460 / 95R25 specification mining wide-body dump truck tire as an example to calculate the tire weight using the simulation analysis method of this invention. A schematic diagram of the tire material design distribution is shown below. Figure 3 As shown, in terms of the materials that make up the tire, it is mainly divided into rubber material component 1 and steel cord component 2. Among them, the steel cord used in steel cord component 2 is all 7×7×0.22+0.15 specification steel cord.

[0031] The tire weight simulation calculation method in this embodiment includes the following steps:

[0032] S1 calculates the cross-sectional area of ​​the rebar unit of the steel cord.

[0033] S1-1: Measured bulk density of steel cord ρ1 = 7.8 × 10⁻⁶ -3 g / mm 3 ;

[0034] S1-2: A 1m length of steel cord was cut and weighed using an analytical balance with an accuracy of 0.001g. The measured linear density of the steel cord was ρ² = 15.2 × 10⁻⁶. -3 g / mm;

[0035] S1-3: Calculate the cross-sectional area of ​​the rebar unit for the steel cord: A = ρ2 / ρ1 = 1.9487 mm 2 ;

[0036] S2 calculates the rebar unit density of steel cord.

[0037] S2-1: The actual measured bulk density of the rubber material bonded to the steel cord, ρ3 = G1 / V = 1.17 × 10⁻⁶, was determined using a densitometer. - 3 g / mm 3 ;

[0038] S2-2: Calculate the rebar unit density of steel cord ρ = ρ1 - ρ3 = 6.63 × 10 -3 g / mm 3 ;

[0039] S3 has a steel cord rebar unit cross-sectional area A = 1.9487 mm². 2 The rebar unit density of the steel cord is ρ = 6.63 × 10⁻⁶. - 3 g / mm 3 Define the tire finite element model in the calculation file, submit the calculation, and read the tire model weight simulation results.

[0040] Comparative Example 1

[0041] Comparative Example 1 uses existing simulation analysis methods to calculate tire weight. Specifically, the cross-sectional area of ​​the rebar element is calculated as the sum of the circular cross-sectional areas of all the steel wires that make up the steel cord; the density of the rebar element is the bulk density of a single steel wire in the steel cord, which is the density of steel, 7.8 × 10⁻⁶. -3 g / mm 3 Define both in the tire finite element model calculation file, submit the calculation, and read the tire model weight simulation results.

[0042] The simulation results of the tire weight calculated using the methods of Example 1 and Comparative Example 1 are shown in Table 1. In the tire simulation analysis, the rubber element is a geometric solid element with volume. The total weight of the rubber element can be calculated using the defined rubber density and the volume defined by the tire geometric model.

[0043] Table 1. Simulation results of tire weight calculation for Example 1 and Comparative Example 1

[0044]

[0045] Example 2

[0046] This embodiment uses a 12.00R24 specification underground mining tire as an example. The tire material design distribution diagram is as follows: Figure 4 As shown, the outermost belt layer uses 3×7×0.22 specification steel cord, while the other steel cord components 2 use (3+9+15)×0.22+0.15 specification steel cord.

[0047] The tire weight simulation calculation method in this embodiment includes the following steps:

[0048] S1 calculates the cross-sectional area of ​​the rebar unit of the steel cord.

[0049] S1-1: The measured bulk density ρ1 of steel cords with specifications of 3×7×0.22 and (3+9+15)×0.22+0.15 is 7.8×10 -3 g / mm 3 ;

[0050] S1-2: A 1m length of 3×7×0.22 gauge steel cord was cut and weighed using an analytical balance with an accuracy of 0.001g. The linear density of the steel cord was measured to be ρ. 2-1 =6.95×10 -3 g / mm; A 1m length of (3+9+15)×0.22+0.15 gauge steel cord was cut and weighed using an analytical balance with an accuracy of 0.001g. The linear density of the steel cord was measured to be ρ. 2-2 =8.5×10 -3 g / mm;

[0051] S1-3: Calculate the cross-sectional area A1 of a 3×7×0.22 gauge steel cord rebar unit. 2-1 / ρ1=0.891mm 2 The cross-sectional area A2 of the rebar unit of the (3+9+15)×0.22+0.15 specification steel cord is calculated as follows: 2-2 / ρ1=1.0897mm 2 ;

[0052] S2 calculates the rebar unit density of steel cord.

[0053] S2-1: The actual measured bulk density of the rubber material bonded to the steel cord, ρ3 = G1 / V = 1.17 × 10⁻⁶, was determined using a densitometer. - 3 g / mm 3 ;

[0054] S2-2: Calculate the rebar unit density of steel cord ρ = ρ1 - ρ3 = 6.63 × 10 -3 g / mm 3 ;

[0055] S3 uses a 3×7×0.22 specification steel cord rebar unit with a cross-sectional area A1=0.891mm². 2 The rebar unit density ρ of 3×7×0.22 specification steel cord is 6.63×10 -3 g / mm 3 Defined in the tire finite element model calculation file; the cross-sectional area A2 of the (3+9+15)×0.22+0.15 specification steel cord rebar element is 1.0897mm². 2 The rebar unit density ρ of (3+9+15)×0.22+0.15 specification steel cord is 6.63×10 -3 g / mm 3 Define it in the tire finite element model calculation file; submit the calculation and read the tire model weight simulation results.

[0056] Comparative Example 2

[0057] Comparative Example 2 uses existing simulation analysis methods to calculate tire weight. Specifically, the cross-sectional area of ​​the rebar element is calculated as the sum of the circular cross-sectional areas of all the steel wires that make up the steel cord; the density of the rebar element is the bulk density of a single steel wire in the steel cord, which is the density of steel, 7.8 × 10⁻⁶. -3 g / mm 3 Define both in the tire finite element model calculation file, submit the calculation, and read the tire model weight simulation results.

[0058] The simulation results of the tire weight calculated using the methods of Example 2 and Comparative Example 2 are shown in Table 2:

[0059] Table 2. Simulation results of tire weight for Example 2 and Comparative Example 2

[0060]

[0061] Example 3

[0062] Taking a 35 / 65R33 engineering tire as an example, the tire material design distribution diagram is as follows: Figure 5As shown, the outermost belt layer uses 4×6×0.25 steel cord; the other belt layers use 7×7×0.22+0.15 steel cord; the carcass uses 7×7×0.25+0.15 steel cord, which has the same structure as the 7×7×0.22+0.15 steel cord, except that the diameter of the steel wires other than the outer winding wire is increased from 0.22mm to 0.25mm.

[0063] The tire weight simulation calculation method in this embodiment includes the following steps:

[0064] S1 calculates the cross-sectional area of ​​the rebar unit of the steel cord.

[0065] S1-1: The measured bulk density ρ1 of steel cords with specifications of 4×6×0.25, 7×7×0.22+0.15, and 7×7×0.25+0.15 is 7.8×10⁻⁶. -3 g / mm 3 ;

[0066] S1-2: A 1m length of 4×6×0.25 gauge steel cord was cut and weighed using an analytical balance with an accuracy of 0.001g. The linear density of the steel cord was measured to be ρ. 2-1 =10.17×10 -3 g / mm; A 1m length of 7×7×0.22+0.15 gauge steel cord was cut and weighed using an analytical balance with an accuracy of 0.001g. The linear density of the steel cord was measured to be ρ. 2-2 =15.2×10 -3 g / mm; A 1m length of 7×7×0.25+0.15 gauge steel cord was cut and weighed using an analytical balance with an accuracy of 0.001g. The linear density of the steel cord was measured to be ρ. 2-3 =19.8×10 -3 g / mm;

[0067] S1-3: Calculate the cross-sectional area A1 of a 4×6×0.25 gauge steel cord rebar unit. 2-1 / ρ1=1.3038mm 2 The cross-sectional area A2 of a 7×7×0.22+0.15 specification steel cord rebar unit is calculated as ρ. 2-2 / ρ1=1.9487mm 2 The cross-sectional area A3 of a 7×7×0.25+0.15 specification steel cord rebar unit is calculated as ρ. 2-3 / ρ1=2.5385mm 2 ;

[0068] S2 calculates the rebar unit density of steel cord.

[0069] S2-1: The actual measured bulk density of the rubber material bonded to the steel cord, ρ3 = G1 / V = 1.17 × 10⁻⁶, was determined using a densitometer. - 3 g / mm 3 ;

[0070] S2-2: Calculate the rebar unit density of steel cord ρ = ρ1 - ρ3 = 6.63 × 10 -3 g / mm 3 ;

[0071] S3 uses a 4×6×0.25 specification steel cord rebar unit with a cross-sectional area A1=1.3038mm². 2 The rebar unit density ρ of 4×6×0.25 specification steel cord is 6.63×10 -3 g / mm 3 Defined in the tire finite element model calculation file; the cross-sectional area A2 of the 7×7×0.22+0.15 steel cord rebar element is 1.9487mm². 2 The rebar unit density ρ of 7×7×0.22+0.15 specification steel cord is 6.63×10 -3 g / mm 3 Defined in the tire finite element model calculation file; the cross-sectional area A3 of the 7×7×0.25+0.15 specification steel cord rebar element is 2.5385mm². 2 The rebar unit density ρ of 7×7×0.25+0.15 specification steel cord is 6.63×10 -3 g / mm 3 Define it in the tire finite element model calculation file; submit the calculation and read the tire model weight simulation results.

[0072] Comparative Example 3

[0073] Comparative Example 3 uses existing simulation analysis methods to calculate tire weight. Specifically, the cross-sectional area of ​​the rebar element is calculated as the sum of the circular cross-sectional areas of all the steel wires that make up the steel cord; the density of the rebar element is the bulk density of a single steel wire in the steel cord, which is the density of steel, 7.8 × 10⁻⁶. -3 g / mm 3 Define both in the tire finite element model calculation file, submit the calculation, and read the tire model weight simulation results.

[0074] The simulation results of the tire weight calculated using the methods of Example 3 and Comparative Example 3 are shown in Table 3:

[0075] Table 3. Simulation results of tire weight calculation for Example 3 and Comparative Example 3

[0076]

[0077] As can be clearly seen from Tables 1-3, this invention improves the accuracy of engineering tire weight simulation calculation by optimizing the calculation method of the cross-sectional area and density of the steel cord rebar unit.

Claims

1. A method for improving the accuracy of engineering tire weight simulation calculations, characterized in that, Includes the following steps: S1 Optimized Calculation Method for Steel Cord Cross-sectional Area: S1-1: Obtain the weight per unit volume of the steel cord, i.e., the bulk density ρ1 of the steel cord; S1-2: The measured weight per unit length of steel cord, i.e., the linear density ρ2 of the steel cord; S1-3: The cross-sectional area of ​​the steel cord is calculated as A = ρ2 / ρ1; Calculation method for S2 steel cord density: S2-1: Obtain the weight per unit volume of the rubber material that is bonded to the steel cord, i.e., the bulk density ρ3 of the rubber material; S2-2: Calculate the linear density of steel cord ρ = ρ1 - ρ3; S3 Tire Simulation Calculation of Steel Cord Rebar Element Parameters: Define the cross-sectional area A of the steel cord obtained in step S1 as the cross-sectional area of ​​the steel cord rebar element, and define the steel cord density ρ calculated in step S2 as the density of the steel cord. Perform tire finite element simulation calculation to obtain the tire weight simulation analysis results.

2. The method for improving the accuracy of engineering tire weight simulation calculation as described in claim 1, characterized in that, The bulk density of the steel cord is ρ1 = 7.8 × 10⁻⁶. -3 g / mm 3 .

Images