JP2013035413A - Prediction method of tire wear energy, and design method of tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To significantly reduce calculation time for calculating a wear energy.SOLUTION: A prediction method of a tire wear energy is provided, which simulates the wear energy of a tire when rolling by using a computer 1. The method includes: a model setting step S1 of inputting a tire model 2 by dividing the tire into the finite number of elements; an acquiring step S2 of acquiring distributions of a ground contact shape and a ground contact pressure by performing static ground contact simulation in which the tire model 2 contacts a virtual road surface 8 based on a boundary condition; a calculation step S3 of calculating intermediate physical values including the ground contact pressure Px, a ground contact length Py in a tire circumferential direction, and a pattern rigidity Pz which are in a region where the wear energy is evaluated; and a calculation step S4 in which the computer 1 calculates the wear energy by substituting the calculated intermediate physical values into a prediction expression for predicting the wear energy using the intermediate physical value obtained by regression analysis.

Description

  The present invention relates to a method for predicting tire wear energy and a method for designing a tire that simulate the wear energy during rolling of a tire in a short time.

  Conventionally, various studies have been made to improve the wear performance of tires, and one of them is a wear simulation for analyzing tire wear characteristics using a computer, for example, in Patent Documents 1 to 3 below. Yes.

  In such a conventional wear simulation, a rolling simulation is performed in which a tire model is set using a finite number of elements, and the tire model is brought into contact with a virtual road surface (road surface model) and rolled. Then, the shearing force and slip generated at the contact portion of the rolling tire model are calculated, and the wear energy is calculated for each element by the product of these.

  However, since the tire rolling simulation described above rolls the tire model, it takes a very long time to calculate and there is a problem that it takes a lot of time to calculate the wear energy. .

JP 2005-271661 A JP 2004-142571 A JP 2006-160159 A

  The present invention has been devised in view of the above problems. A static ground simulation is performed without rolling a set tire model, and the ground shape and ground obtained by the static ground simulation are calculated. Compared to conventional methods, it is based on the use of intermediate physical quantities calculated from the pressure distribution and prediction formulas that can be used to predict wear energy from intermediate physical quantities that are stored in advance in the computer and obtained by regression analysis. An object of the present invention is to provide a method for predicting the wear energy of a tire that simulates the wear energy during rolling of the tire over time.

  The invention according to claim 1 of the present invention is a tire wear energy prediction method for simulating the wear energy at the time of rolling of a tire using a computer, and the computer has a tread pattern. A model setting step of inputting a tire model having a tread pattern portion by dividing a tire into a finite number of elements, and the computer contacts the tread pattern portion of the tire model with a virtual road surface based on a predetermined boundary condition Performing a static grounding simulation to obtain a grounding shape and a distribution of grounding pressure of the tread pattern unit, and the computer is predetermined from the grounding shape and grounding pressure distribution among the tread pattern unit. Contact pressure in the area where wear energy is evaluated, contact length in the tire circumferential direction, and A calculation step for calculating at least one of intermediate physical quantities including pattern rigidity, and a prediction formula that allows the computer to predict wear energy from the intermediate physical quantities stored in advance in the computer and obtained by regression analysis, And a calculation step of calculating wear energy by substituting the calculated intermediate physical quantity.

  According to a second aspect of the invention, the contact pressure is an average contact pressure neglecting a contact pressure equal to or lower than a predetermined threshold for the elements included in the region. Is the method.

  The invention according to claim 3 is the tire wear energy prediction method according to claim 2, wherein the average contact pressure is calculated by a weighted average.

  According to a fourth aspect of the present invention, the contact length is a maximum length in the tire circumferential direction or an average length in the tire axial direction. The tire wear energy prediction according to any one of the first to third aspects. Is the method.

  In the invention according to claim 5, the pattern rigidity is calculated by a ratio F / L of a force F acting on a land portion of the tread pattern portion and a deformation amount L of the land portion deformed by the force F. The tire wear energy prediction method according to any one of claims 1 to 4.

  The invention according to claim 6 is the invention according to any one of claims 1 to 4, wherein the pattern rigidity is calculated by a physical quantity including a cross-sectional second moment, an elastic modulus, and a shear elastic modulus of a land portion of the tread pattern portion. This is a method for predicting the wear energy of tires.

  The invention according to claim 7 is the tire wear energy prediction method according to claim 5 or 6, wherein the pattern rigidity is unit pattern rigidity per unit area of the tread pattern portion.

  The invention according to claim 8 is the tire wear energy prediction method according to any one of claims 1 to 7, wherein in the calculation step, all of the three intermediate physical quantities are calculated.

  In the invention according to claim 9, the wear energy at the time of rolling of the tire predicted by the method for predicting wear energy of the tire according to any one of claims 1 to 8 is equal to or less than a predetermined allowable wear energy. The method for designing a tire includes a step of changing the tread pattern portion of the tire model until the time reaches, and a step of designing a tread pattern of the tire based on the tread pattern portion.

  According to the method of predicting the wear energy of a tire by simulating the wear energy during rolling of the tire of the present invention using a computer, the tire having a tread pattern is divided into a finite number of elements in the computer. A model setting step of inputting a tire model having a tread pattern portion, and the computer performs a static grounding simulation for bringing the tread pattern portion of the tire model into contact with a virtual road surface based on a predetermined boundary condition, and the tread An acquisition step of acquiring a ground shape of the pattern portion and a distribution of the ground pressure, and grounding of a region in which the computer evaluates a predetermined wear energy in the tread pattern portion from the ground shape and the ground pressure distribution. Intermediate including pressure, tire circumferential contact length and pattern stiffness A calculation step for calculating at least one of the quantities; and the calculated intermediate physical quantity in a prediction formula that allows the computer to predict wear energy from the intermediate physical quantity stored in advance in the computer and obtained by regression analysis. And calculating a wear energy by substituting.

  That is, in the method for predicting the wear energy of the tire according to the present invention, an intermediate physical quantity in a region where the wear energy is evaluated is calculated from the contact shape and contact pressure of the tread pattern portion acquired by the static contact simulation. Then, the wear energy is calculated by substituting the calculated intermediate physical quantity into a prediction formula that can be predicted from the intermediate physical quantity that is stored in advance in the computer and obtained by regression analysis. Such a method for predicting wear energy can calculate the wear energy in a short time from the result of the static contact simulation without rolling the tire model. Therefore, according to the present invention, the wear energy can be predicted in a short time as compared with the method of predicting the wear energy from the conventional rolling simulation.

It is a flowchart which shows an example of the process sequence of this invention. It is a perspective view of the computer apparatus which performs the process of this invention. It is sectional drawing which visualizes and shows an example of a tire model. It is the earthing | grounding shape figure of the tread pattern part. FIG. 4 is a partially enlarged view of FIG. 3. It is sectional drawing of the tire model explaining a boundary condition. It is an expanded view of the tread pattern part which visualizes and shows an abrasion characteristic. It is a figure showing the correlation of the wear energy by the method of this invention, and the wear energy by rolling simulation.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows an embodiment of a procedure of a tire design method including a method for predicting tire wear energy according to the present invention. The method for predicting the wear energy of the tire according to the present embodiment is a method of simulating the wear energy at the time of rolling of the tire using the computer 1, which includes a model setting step S 1 for inputting the tire model to the computer, Step S2 for obtaining a contact shape and contact pressure distribution of the tread pattern portion, calculating step S3 for calculating at least one intermediate physical quantity from the contact shape and contact pressure distribution, and the calculation And a calculation step S4 for calculating the wear energy by substituting the intermediate physical quantity.

  FIG. 2 shows the computer 1 for carrying out the present invention. The computer 1 includes a main body 1a, a keyboard 1b as input means, a mouse 1c, and a display device 1d as output means. Although not shown in the figure, the main body 1a appropriately includes an arithmetic processing unit, a memory, a magnetic disk, a CD-ROM, a flexible disk drive 1a1, 1a2, and the like as is well known. The magnetic disk stores a program for executing a tire simulation method. As the computer 1, a high-speed EWS, a supercomputer, or the like is preferable.

  In the model setting step S1, a tire model 2 having a tread pattern portion 3 by dividing a tire (pneumatic tire) having a tread pattern into a finite number of elements is input to the computer 1. The tire model 2 is actually numerical data handled by the computer 1, but FIG. 3 shows a cross-sectional view visualizing it.

  The tire model 2 is modeled by dividing the tire to be analyzed into a finite number of small elements 2a, 2b, 2c. The tire to be analyzed may be a real tire or a non-existing design stage. The tire model 2 of the present embodiment is a model that is modeled on a heavy duty radial tire (mold shape) at the design stage.

  The elements 2a, 2b, 2c,... Constituting the tire model 2 are determined so that numerical analysis is possible. The possibility of numerical analysis means that calculation is possible according to a numerical analysis method such as a finite element method, a finite volume method, a difference method, or a boundary element method. Specifically, for each element 2a, 2b, 2c..., A nodal coordinate value, a shape, a material characteristic (for example, density, elastic modulus, loss tangent or damping coefficient) and the like are defined. Each of the elements 2a, 2b, 2c,... Is formed of, for example, a triangular or quadrangular film element as a two-dimensional plane, and a three-dimensional element, for example, a tetrahedral or hexahedral solid element. The tire model 2 has a tread pattern portion 3. In other words, the three-dimensional shape is incorporated in the model by dividing the tread pattern of the tire at the design stage to be modeled into a finite number of elements.

  FIG. 4 shows an example of a grounding shape in which the tread pattern portion 3 of the tire model 2 is grounded on a plane. In this figure, elements are not shown for the longitudinal groove 4 and the lug groove 5 for easy understanding. Such a tread pattern portion 3 includes at least one longitudinal groove 4 extending in the tire circumferential direction and a plurality of lug grooves 5 that terminate without extending between the longitudinal grooves 4.

  The longitudinal groove 4 of the present embodiment has a pair of central longitudinal grooves 4a, 4a extending continuously in the tire circumferential direction on the most tire equator side, and the tire axial direction outer side of the central longitudinal groove 4a is continued in the tire circumferential direction. And a pair of outer vertical grooves 4b, 4b extending. As a result, the tread pattern portion 3 is divided into a plurality of ribs 6 formed between the longitudinal grooves 4 and 4. The rib 6 of this embodiment includes a crown rib 6a, a middle rib 6b, and a shoulder rib 6c that are sequentially arranged from the tire equator side toward the tire axial direction outer side. The specific shape and arrangement of the grooves are not limited to the illustrated example.

  The outer surface in the tire radial direction of each rib 6 is defined as a tread surface 3A that contacts the road surface. The tread surface 3A of the tire model 2 is configured by a continuous body of element surfaces that form a triangle or a quadrangle surrounded by three or four adjacent nodes. Further, contact between the tread surface 3A and a virtual road surface 8 described later is considered.

  FIG. 5 shows a partially enlarged view of the tread pattern portion 3 of FIG. The tread pattern portion 3 is a portion on the outer side in the tire radial direction from a line passing through the groove bottom of the outer vertical groove 4b having the largest groove depth. In this embodiment, the main portion of the tread pattern portion 3, specifically, the portion between the outer ends in the tire axial direction of the shoulder rib 6c is substantially parallel to the tread surface 3A that is in contact with the road surface and has a small thickness. Is shown as modeled in layers using element 7 of

  The element 7 is formed of a hexahedral solid element having a low aspect ratio with a small thickness in the tire radial direction in the present embodiment. The element 7 is not limited to a hexahedron as long as it is layered, and may be various elements such as a tetrahedron. When the thickness t1 of each element 7 is decreased, the number of elements may be remarkably increased and the calculation time may be increased. Conversely, when the thickness t1 is increased, the siping or tie bar is shallow in the depth direction of the groove. The thickness t1 is preferably 3 to 50% of the groove depth d of the central vertical groove 4a having the largest thickness.

  Next, in this embodiment, the acquisition step S2 includes a boundary condition setting step S2a in which a boundary condition necessary for the tire model 2 is set, and a simulation step S2b in which a static ground simulation is performed based on the boundary condition. Including. As the boundary condition, for example, a condition regarding a rim on which the tire model 2 is mounted, a condition regarding a filled air pressure, a condition regarding a load to be applied, and the like are set.

  As shown in FIG. 6, the rim-related conditions are parameters necessary for the tire model 2 to reproduce the rim assembly state. Specifically, the rim contact areas 2B, 2B where the tire model 2 contacts the rim, Definition of a constraint that makes the rim contact area 2B undisplaceable, a width BW between the rim contact areas 2B and 2B (normally, this is equal to the rim width BW of the applied rim), a virtual rotation axis CL of the tire model 2, And a relative distance rr (always constant at the rim radius) between the rotation axis CL and the rim contact area 2B. Further, as a condition relating to the air pressure, an evenly distributed load w corresponding to the air pressure to be analyzed over the entire inner surface of the tire model 2 is defined. As a load condition to be loaded, a value of the vertical load I that pushes down the rotation axis CL of the tire model 2 vertically and / or a static friction coefficient between the virtual road surface 8 and the like are set.

  The model setting step for setting the tire model 2 and the setting of the boundary condition are normally set as appropriate while taking into account the user's desire while using the computer 1.

  In the simulation step S2b, a static ground simulation is performed in which the tire model 2 is grounded on the virtual road surface 8 based on the predetermined boundary condition. Then, from the simulation, the contact shape of the tread pattern portion 3 and the distribution of contact pressure are acquired.

The virtual road surface 8 is a model of a road surface on which a tire travels. In the present embodiment, the virtual road surface 8 is modeled by a flat rigid element arranged horizontally.
In the static ground simulation, the ground shape of the tread pattern portion 3 and the distribution of the ground pressure are calculated by grounding the virtual road surface 8 based on the boundary condition without rolling the tire model 2. That is, the static deformation state of the tire model 2 is calculated. In this calculation, if the tire model 2 and the boundary conditions can be set, based on such information, for example, general-purpose finite element analysis application software (for example, application software manufactured by Livermore Software Technology (LSTC), USA) This is performed using the computer 1 by “LS-DYNA” or the like.

  By performing such a static contact simulation, the contact shape and contact pressure distribution of the tread pattern portion 3 can be acquired, and a location where the tread pattern portion 3 is likely to be worn or a location where wear is difficult can be identified. .

  FIG. 7 shows a partial development view of the tread pattern portion 3 visualized by converting the contact shape and contact pressure distribution of the tread pattern portion 3 into saturation information. In this figure, the region where the contact pressure above a certain threshold is applied is displayed in white. That is, the change in the magnitude of the ground pressure is shown in gray and white. In this result, a large ground pressure acts on the central portion including the crown rib 6a and the middle rib 6b and the central portion of the shoulder rib 6c.

  In the calculation step S3, the computer 1 calculates an intermediate physical quantity of a region in the tread pattern portion 3 where a predetermined wear energy is evaluated from the contact shape and contact pressure distribution. Here, the “region” may be, for example, the entire region of the tread surface 3 </ b> A including all the ribs 6, a region in at least one of the ribs 6 a to 6 c, or a single rib 6. May be divided into regions in the tire axial direction and / or the tire circumferential direction.

  Further, the intermediate physical quantity includes a contact pressure Px, a contact length Py in the tire circumferential direction, and a pattern rigidity Pz, and if at least one intermediate physical quantity is calculated from a contact shape and a contact pressure in a region where wear energy is evaluated. good.

  The contact pressure Px is used as an index of the force acting on the land portion (rib 6) of the tread pattern portion 3 at the time of tire rolling. Such a contact pressure Px is preferably an average contact pressure Px1 ignoring a contact pressure equal to or lower than a predetermined threshold for the elements included in the region. That is, the contact pressure below the threshold value has little influence on wear, and if the average contact pressure including this part is calculated, the contact pressure may be underestimated. Therefore, by ignoring the contact pressure below the threshold value, it is possible to obtain a contact pressure suitable for predicting the wear energy of the tire. For example, in the case of a heavy load tire, the threshold value is preferably 0.09 to 0.13 MPa, and in the case of a passenger car tire, the threshold value is 0.05 to 0.08 MPa. desirable.

  The average contact pressure Px1 is preferably calculated by a weighted average weighted by the size of the element in the region. As a result, the contact pressure suitable for predicting the wear energy of the tire can be obtained.

  The contact length Py is used as an index of the time from when the land portion (rib 6) of the tread pattern portion 3 contacts the ground to when the tire rolls. For example, as shown in FIG. 7, the contact length Py is the maximum length Py1 in the tire circumferential direction in the contact shape (each rib 6) in the region or the average length Py2 in the tire axial direction of each rib 6 ( (Not shown). Further, the contact length Py may be substituted by the tire circumferential length Py3 at the center in the tire axial direction.

  The pattern rigidity Pz is used as an index of distortion due to a force acting on the land portion (rib 6) of the tread pattern portion 3 during tire rolling. The pattern rigidity Pz is calculated by a ratio F / L between the force F acting on the rib 6 of the tread pattern portion 3 and the deformation amount L of the rib 6 deformed in the direction of the force by the force F. desirable.

Such pattern rigidity Pz is preferably calculated by physical quantities including, for example, the secondary moment of section I, the elastic modulus E, and the shear elastic modulus G of the land portion of the tread pattern portion 3. A specific calculation formula for calculating the pattern rigidity Pz is as the following formula (1).
Pz = F / L = 1 / (h ³ / (3 × E × I) + h / (S × G)) (1)
Indicated by As shown in FIG. 5, “h” in the equation (1) indicates the height of the land portion in the tire radial direction, that is, the groove depth d of the longitudinal groove 4 adjacent to the rib 6, and “S "Represents the surface area of the land (rib 6).

  More preferably, the pattern rigidity Pz is calculated as a unit pattern rigidity per unit area of the tread surface 3A of the tread pattern portion 3. According to such unit pattern rigidity, since the pattern rigidity of the land portion of the tread pattern portion 3 provided with a large number of sipings and the like can be reduced, it is useful for appropriately calculating the wear energy in the next step.

  Next, the calculation step S4 is performed. In the calculation step S4, the computer 1 uses a prediction formula for predicting the wear energy stored in advance in the computer 1, and the value of the wear energy P1 is calculated by substituting the calculated intermediate physical quantity into this prediction formula. . Such a prediction formula is obtained by, for example, regression analysis or multiple regression analysis of the calculated intermediate physical quantity and the wear energy P2 calculated by the rolling simulation.

  The wear energy P2 calculated by the rolling simulation is the product of the acting force and the amount of slip for each element of the rolling tread surface 3A until the element leaves the road surface and leaves. In the meantime, it is calculated as a physical quantity calculated in minute time increments and summed up. In this rolling simulation, in the tread pattern portion 3 of the tire model 2, at least all the nodes appearing on the tread surface 3A, the shearing forces in the X and Y directions received during the ground contact and the slip amount with respect to the acting direction of each shear force The wear energy P2 is calculated by multiplying these values.

The prediction formula varies depending on the type of the calculated intermediate physical quantity. For example, when the wear energy P1 is predicted only by the contact pressure,
A prediction formula of P1 = 72.6 × Px-179.8 is adopted.
For example, when the wear energy P1 is predicted only by the contact length,
A prediction formula of P1 = 0.73 × Py−38.4 is employed.
For example, when the wear energy P1 is predicted only by the pattern rigidity,
A prediction formula of P1 = −106.2 × Pz + 152.2 is adopted.
For example, when the wear energy P1 is predicted by the contact pressure and the contact length,
A prediction formula of P1 = 61.0 × Px + 0.53 × Py-218.1 is employed.
For example, when the wear energy P1 is predicted by the contact pressure and the pattern rigidity,
A prediction formula of P1 = 72.1 × Px−11.8 × Pz−168.8 is employed.
For example, when the wear energy P1 is predicted by the pattern rigidity and the contact length,
A prediction formula of P1 = 0.87 × Py-213.7 × Pz + 106.8 is employed.

  As described above, the method for predicting the wear energy of the tire according to the present invention calculates the intermediate physical quantity of the region where the wear energy is evaluated from the contact shape and the contact pressure of the tread pattern portion 3 acquired by the static contact simulation. Then, the wear energy P1 is calculated by substituting the calculated intermediate physical quantity into a prediction formula that can be stored in advance in the computer and that can predict the wear energy from the intermediate physical quantity obtained by regression analysis. Such a method for predicting the wear energy can calculate the wear energy in a short time from the result of the static contact simulation without rolling the tire model 2. Therefore, according to the present invention, the wear energy can be predicted in a shorter time than the method of predicting the wear energy P2 from the conventional rolling simulation.

Further, the inventors have found from the results of various experiments that the calculation step preferably calculates all the three intermediate physical quantities. Then, it was found that by using the following prediction formula (2), a result having a high correlation with the wear energy obtained by the rolling simulation is obtained. Such a prediction formula (2) is
P1 = A × (Px) ² + B × Px + C × Py + D × Pz + E (2)
It is represented by Each coefficient A to E is a coefficient obtained by multiple regression analysis of the calculated three intermediate physical quantities and the wear energy P2 calculated by the rolling simulation.
The units of wear energy P1, contact pressure Px, contact length Py, and pattern rigidity Pz are:
P1: J / m ²
Px: kgf / cm ²
Py: mm
Pz: N / mm / mm ²
Is adopted.

The inventors obtained the wear energy P2 by the rolling simulation, the contact pressure Px, the contact length Py in the tire circumferential direction and the intermediate physical quantity for calculating the pattern stiffness Pz by substituting them into the prediction formula (2). In order to confirm the correlation with the wear energy P1, a test was performed using the wear energy prediction method based on the rolling simulation and the wear energy prediction method of the present invention. Three types of tire sizes, 225 / 50R17, 235 / 60R18, and 235 / 50R18, are used, and the specifications of the rim 7.5J, the internal pressure 230 kPa, and the speed 20 km / h are common. The 225 / 50R17 tire has a load of 6 kN or 8 kN, the 235 / 60R18 tire has a load of 7 kN or 9 kN, and the 235 / 50R18 tire has a load of 4.29 kN or 5.34 kN. Was loaded. The coefficients A to E were as follows.
A: 21.8
B: -107
C: 0.65
D: -111.5
E: 169

  As a result of the test, as shown in FIG. 8, it can be understood that the wear energy P1 by the wear energy prediction method according to the present invention has a correlation with the wear energy P2 by the conventional wear energy prediction method. Moreover, the calculation time of the wear energy P1 by the prediction method of the present invention was 10% of the calculation time of the wear energy P2 by the conventional rolling simulation. That is, it can be understood that the time required for the prediction method of the present invention can be reduced by about 90% compared to the time required for the conventional rolling simulation. Therefore, it can be understood that the prediction method of the present invention is more useful than the conventional prediction method.

  Next, a tire design method using the method for predicting tire wear energy according to the present invention will be described.

  The tire design method according to the present embodiment is a tread pattern portion of the tire model 2 until the wear energy during rolling of the tire predicted by the above-described wear energy prediction method is equal to or less than a predetermined allowable wear energy. 3 including step S5 of changing 3. That is, in this step S5, the model setting step S1 to the calculation step S4 are repeatedly performed until the wear energy P1 obtained by calculation becomes equal to or less than the allowable wear energy.

  As the allowable wear energy, a value of wear energy obtained experimentally from a tire having good wear resistance is used. This makes it possible to easily design a tire with good wear resistance.

  Next, a tread pattern of the tire is designed based on the tread pattern portion 3 that has become the allowable wear energy or less.

  Thus, in the tire design method of the present embodiment, the wear energy prediction method of the present invention is used every time the tread pattern portion 3 is changed. As a result, the tread pattern of the tire can be designed in a very short time compared to the conventional tire design method in which the tire rolling simulation is repeated.

  The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the illustrated embodiments, and can be implemented in various forms.

1 Computer 2 Tire Model 8 Virtual Road Surface Px Ground Pressure Py Ground Length Pz Pattern Rigidity S1 Model Setting Step S2 Acquisition Step S3 Calculation Step S4 Calculation Step

Claims (9)

A method for predicting tire wear energy by simulating tire wear energy using a computer,
A model setting step of inputting a tire model having a tread pattern portion by dividing a tire having a tread pattern into a finite number of elements on the computer;
The computer performs a static contact simulation in which the tread pattern portion of the tire model is brought into contact with a virtual road surface based on a predetermined boundary condition, and acquires a contact shape and a distribution of contact pressure of the tread pattern portion. When,
From the contact shape and contact pressure distribution, the computer calculates intermediate physical quantities including the contact pressure, the contact length in the tire circumferential direction, and the pattern rigidity in a region where a predetermined wear energy is evaluated in the tread pattern portion. A calculating step for calculating at least one;
A calculation step in which the computer calculates wear energy by substituting the calculated intermediate physical quantity into a prediction formula that can be stored in the computer in advance and that can predict wear energy from the intermediate physical quantity obtained by regression analysis; A method for predicting tire wear energy.   The tire contact energy prediction method according to claim 1, wherein the contact pressure is an average contact pressure neglecting a contact pressure equal to or lower than a predetermined threshold value for elements included in the region.   The tire wear energy prediction method according to claim 2, wherein the average contact pressure is calculated by a weighted average.   The tire contact energy prediction method according to any one of claims 1 to 3, wherein the contact length is a maximum length in a tire circumferential direction or an average length in a tire axial direction.   5. The pattern rigidity is calculated by a ratio F / L between a force F acting on a land portion of the tread pattern portion and a deformation amount L of the land portion deformed by the force F. 6. The prediction method of the wear energy of the tire as described in 2.   The tire stiffness energy prediction method according to any one of claims 1 to 4, wherein the pattern rigidity is calculated by a physical quantity including a cross-sectional second moment, an elastic modulus, and a shear elastic modulus of a land portion of the tread pattern portion.   The method for predicting tire wear energy according to claim 5 or 6, wherein the pattern stiffness is unit pattern stiffness per unit area of the tread pattern portion.   The method for predicting tire wear energy according to claim 1, wherein all of the three intermediate physical quantities are calculated in the calculating step. The tire model of the tire model until the wear energy at the time of rolling of the tire predicted by the method for predicting the wear energy of the tire according to any one of claims 1 to 8 is equal to or less than a predetermined allowable wear energy. Including a step of changing the tread pattern portion,
A tire designing method comprising a step of designing a tread pattern of a tire based on the tread pattern portion.

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