JP2006309437A - Device and method for simulating tire characteristic, and method for forming tire model - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device and a method for simulating tire characteristics, capable of increasing the prediction accuracy for tire characteristics, and a method for forming a tire model. <P>SOLUTION: In this simulation device 1 for tire characteristics, in forming a tire model, the influence on an abnormal deformation of an element by setting change of characteristic parameters of a plurality of parts constituting a tire is evaluated for each part. The influence on a characteristic value related to a tire characteristic by changing settings of characteristic parameters of the parts is then evaluated. Based on the evaluation results obtained by the element deformation evaluation means and the characteristic value sensitivity evaluation means, a part having a high suppressing effect of the abnormal deformation of the element and a minimum influence on the change of the characteristic value related to the tire characteristic is selected. The characteristic parameter of the selected parts is set so that the abnormal deformation of the element can be suppressed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a tire characteristic simulation apparatus and method, and a tire model creation method, and more particularly, to provide a tire characteristic simulation apparatus and method and tire model creation method that can improve the prediction accuracy of tire characteristics. About.

  In recent years, a method of predicting tire characteristics by computer simulation using numerical analysis has been widely adopted. In such tire characteristic simulation, a tire model is created by dividing a three-dimensional shape of a tire into a plurality of finite elements, and a numerical simulation is performed using the tire model. For this reason, in order to improve the prediction accuracy of tire characteristics, it is required to create a tire model with higher accuracy.

  In this problem, a technique described in Patent Document 1 is known as a conventional tire characteristic simulation apparatus. In the conventional tire characteristic simulation apparatus, a tire model that approximates a three-dimensional shape of a tire by dividing it into a finite number of elements is analyzed using a finite element method to simulate tire performance. In the simulation apparatus, a two-dimensional model is created by dividing the two-dimensional CAD data of the tread portion of the patterned tire into a plurality of elements composed of at least one of a quadrilateral element and a triangular element, and on the axis intersecting with the two-dimensional model. Means for sweeping the two-dimensional model to create a three-dimensional model composed of at least one of a pentahedral element and a hexahedral element; and means for creating a model of a tire case part including a belt and a carcass part; The cross-sectional shape of the three-dimensional model is changed along the surface of the tire case model. A means for creating a tire model by attaching the changed model to the model of the tire case portion, and applying at least one of predetermined internal pressure, load, and forced speed to the tire model as a condition, and using a finite element method And means for simulating the performance of the tire.

JP 2001-282873 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide a tire characteristic simulation apparatus and method, and a tire model creation method that can improve prediction accuracy of tire characteristics.

  In order to achieve the above object, a tire characteristic simulation device according to the present invention includes a means for creating a tire model by dividing a tire shape composed of a plurality of parts into a plurality of elements, and a tire characteristic for the tire model. An apparatus for simulating tire characteristics including means for performing a simulation on element deformation evaluation means for evaluating the influence exerted on abnormal deformation of the element by changing the setting of characteristic parameters of the parts for each part, and Based on the evaluation result obtained by the characteristic value sensitivity evaluation means for evaluating the influence on the characteristic value related to the tire characteristics by the setting change of the characteristic parameter of the parts, and the evaluation result obtained by the element deformation evaluation means and the characteristic value sensitivity evaluation means, The effect of suppressing abnormal deformation of the element is great, and the characteristic value related to tire characteristics A part selection means for selecting a part effect is small for reduction, as abnormal deformation of the element is suppressed, characterized in that it comprises a parameter setting means for setting the characteristic parameters of the selected said part.

  In this tire characteristic simulation device, among the plurality of parts constituting the tire model, when the characteristic parameter setting is changed, the influence on the effect of suppressing abnormal deformation of the element is large, and the characteristic value related to the tire characteristic is A part having a small influence on the change is selected, and the characteristic parameters of the selected part are adjusted so that abnormal deformation of the element is suppressed. In such a configuration, since it is possible to suppress abnormal deformation of the elements while reducing the influence on the tire characteristic value, it is possible to create a highly accurate tire model. Thereby, there exists an advantage which the prediction precision of a tire characteristic increases. The shape of the tire is not limited to a three-dimensional shape, and may be a tire cross-sectional shape or other two-dimensional shapes.

  Further, in the tire characteristic simulation apparatus, the evaluation by the element deformation evaluation means is performed based on the hour glass energy E accumulated in the parts.

  In this tire characteristic simulation apparatus, the evaluation in the element deformation evaluation step is performed based on the hour glass energy accumulated in each part, and therefore, there is an advantage that the abnormal deformation of the element is appropriately determined.

  Further, in the tire characteristic simulation apparatus, the occurrence of abnormal deformation of the element is determined by comparing the hourglass energy E accumulated in the part with the internal energy U.

  In this tire characteristic simulation device, when determining the tire model, the occurrence of abnormal deformation of the element is determined by comparing the hourglass energy accumulated in each part with the internal energy. There is an advantage that is properly judged.

  In the tire characteristic simulation apparatus, at least one of the elastic modulus of the part and the hourglass parameter of the part is included in the characteristic parameter.

  In this tire characteristic simulation apparatus, since at least one of the elastic modulus of the part or the hourglass parameter of the part is included in the part characteristic parameter, the number of elements of the tire model is increased to suppress abnormal deformation of the element. In comparison, there is an advantage that the calculation time required for the simulation is shortened.

  In the tire characteristic simulation apparatus, the characteristic parameter is selected so that the characteristic value related to the tire characteristic is optimized.

  In the tire characteristic simulation apparatus, since the characteristic parameters (design variables) of the parts are selected so that the characteristic value (objective function) related to the tire characteristics is optimized, there is an advantage that the prediction accuracy of the tire characteristics is improved. A technique known to those skilled in the art is employed as the optimization technique.

  Further, in the tire characteristic simulation device, the characteristic value related to the tire characteristic is a tire bending characteristic when a predetermined internal pressure and a predetermined load are applied, and the characteristic parameter includes an elastic modulus.

  In this tire characteristic simulation device, the characteristic value related to the tire characteristic is the deflection characteristic of the tire when a predetermined internal pressure and a predetermined load are applied, and the characteristic parameter of the part includes the elastic modulus of the part. Reproducibility accuracy related to shape and ground pressure distribution is improved. Thereby, there exists an advantage which the prediction precision of a tire characteristic improves.

  The tire characteristic simulation apparatus is applied to a tire model of a tire to which an internal pressure of 500 [kPa] or more is applied.

  For example, in tires such as truck and bus tires that are loaded with a high internal pressure during inflation, abnormal deformation of elements tends to occur in the created tire model. Therefore, by using the tire model of such a tire as an application target, there is an advantage that the effect of improving the prediction accuracy of the tire characteristics can be favorably obtained.

  The tire characteristic simulation method includes a step of creating a tire model by dividing a tire shape including a plurality of parts into a plurality of elements, and a step of performing a simulation on the tire characteristic with respect to the tire model. A method for simulating tire characteristics, wherein an element deformation evaluation step is performed for each part to evaluate the influence of an abnormal deformation of the element due to the setting change of the characteristic parameter of the part, and the setting change of the characteristic parameter of the part The characteristic value sensitivity evaluation step in which the influence on the characteristic value related to the tire characteristic is evaluated by, and the abnormal deformation of the element based on the evaluation result obtained by the element deformation evaluation means and the characteristic value sensitivity evaluation means The effect of suppressing tires is large and changes in characteristic values related to tire characteristics A parts selection step of influence is small part is selected, as abnormal deformation of the element is suppressed, characterized in that it comprises a parameter setting step of setting the characteristic parameters of the selected said part.

  Further, the tire model creating method is a tire model creating method for creating a tire model by dividing a tire shape composed of a plurality of parts into a plurality of elements, and the tire model is created by changing the characteristic parameters of the parts. An element deformation evaluation step in which the influence on the abnormal deformation of the element is evaluated for each part, and a characteristic value sensitivity evaluation step in which the influence on the characteristic value related to the tire characteristic is evaluated by changing the setting of the characteristic parameter of the part. And, based on the evaluation results obtained by the element deformation evaluation means and the characteristic value sensitivity evaluation means, there is a part that has a large effect of suppressing abnormal deformation of the element and a small influence on the change of the characteristic value related to tire characteristics. The selected part selection step and the selected part so that abnormal deformation of the element is suppressed. Characterized in that it comprises a parameter setting step of setting the characteristic parameters.

  According to the tire characteristic simulation apparatus and method and the tire model creation method according to the present invention, an abnormal deformation of an element when a setting of the characteristic parameter is changed among a plurality of parts constituting the tire model. Parts that have a large influence on the suppression effect and a small influence on the change in characteristic values related to tire characteristics are selected, and the characteristic parameters of the selected parts are adjusted so that abnormal deformation of the elements is suppressed. The abnormal deformation of the element can be suppressed while reducing the influence on the characteristic value. This makes it possible to create a highly accurate tire model, which has the advantage of increasing the accuracy of predicting tire characteristics.

  Hereinafter, the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments. The constituent elements of this embodiment include those that can be easily replaced by those skilled in the art or those that are substantially the same. In addition, a plurality of modifications described in this embodiment can be arbitrarily combined within a range obvious to those skilled in the art.

  FIG. 1 is a block diagram showing a tire characteristic simulation apparatus. 2 and 3 are flow charts showing a tire characteristic simulation method. FIG. 4 is a cross-sectional view showing an example of a tire. FIG. 5 is a perspective view showing an example of a tire model. 6 and 7 are explanatory diagrams illustrating an example of the optimization process.

[Tire characteristics simulation device]
The tire characteristic simulation device 1 includes a control device 2, an input device 3, and an output device 4. The control device 2 includes a tire model creation unit 21 and a simulation unit 22 and is configured by, for example, a PC (Personal Computer). The tire model creation unit 21 has a function of creating the tire model 20 (temporary creation and correction). In addition, the tire model creation unit 21 includes an element deformation evaluation unit that performs an element deformation evaluation step ST41, a characteristic value sensitivity evaluation unit that performs a characteristic value sensitivity evaluation step ST42, a part selection unit that performs a part selection step ST43, and parameter setting. Parameter setting means for performing step ST44 (not shown). These steps ST41 to ST44 will be described later.

  The simulation unit 22 performs a predetermined simulation related to tire characteristics. The input device 3 includes a data input unit 31 and a test condition input unit 32, and includes, for example, a keyboard, a mouse, and the like. The data input unit 31 is a means for inputting conditions (tire design conditions, part selection, characteristic parameter setting change, etc.) necessary for creating the tire model 20. The test condition input unit 32 is a means for inputting test conditions necessary for simulation of tire characteristics. The output device 4 has a function of outputting a simulation result (prediction result of tire characteristics), and is configured by, for example, a monitor.

  In the tire characteristic simulation apparatus 1, tire characteristic simulation is performed as follows (see FIGS. 1 to 5).

  First, the tire model 20 of the tire 10 to be simulated is created (temporarily created) (ST1). In general, the tire 10 includes a bead core 11, a bead filler 12, a carcass layer 13, a belt layer 14, an under tread 15, a cap tread 16, and a side tread 17 (see FIG. 4). In creating the tire model 20, the tire 10 is divided into a plurality of parts. For example, the tire 10 is divided into a tread pattern portion having a cap tread 16, a tire casing portion including an undertread 15, and other parts. Then, the three-dimensional shape of each part is modeled by being divided into a plurality of finite elements. Then, the tire model 20 is created by combining the modeled parts (see FIG. 5).

  Next, a tire characteristic simulation is performed using the temporarily created tire model 20 (ST2). In the simulation of tire characteristics, for example, predetermined test conditions relating to vertical stress, shear stress, and the like are input to the tire model 20, and a prediction result of tire performance is calculated based on this. The tire characteristics include, for example, traveling performance, braking performance, cornering performance, and the like with respect to road surface conditions (dry road surface, wet road surface, snow road surface, and the like).

  Here, in the tire model 20 of the tire 10 filled with a high internal pressure, there is a problem that an abnormal deformation of an element (a finite element constituting each part of the tire 10) easily occurs during simulation. Such abnormal deformation of the element occurs, for example, due to hour glass deformation of the element (a phenomenon in which the element is deformed into an hourglass shape), which causes a decrease in simulation accuracy and inability to perform inflation calculation. In particular, from the viewpoint of improving the calculation efficiency of the simulation, when numerical integration is performed using only one point at the center of the element (a one-point integration element is adopted), abnormal deformation (hour glass deformation) of the element is likely to occur. .

  Therefore, in the tire characteristic simulation apparatus 1, the tire model is determined (ST3), and the tire model 20 is corrected in a predetermined case (ST4).

  The determination (ST3) of the tire model 20 is performed based on the simulation result or the obtained prediction accuracy of the tire characteristics. For example, when the absolute value of the difference between the simulation result and the predetermined target value is equal to or less than the predetermined threshold ε and the abnormal deformation of the element is substantially zero, the created tire model 20 is appropriate. It is judged that there is. On the other hand, when such a condition is not satisfied, it is determined that the created tire model 20 is inappropriate, and the tire model 20 is corrected (ST4). Then, simulation (ST2) is performed again using the corrected tire model 20, and tire characteristics are acquired.

  In the correction of the tire model (ST4), first, the influence exerted on the abnormal deformation of the element by changing the setting of the characteristic parameter of the part is evaluated for each part (element deformation evaluation step ST41). In other words, it is evaluated for each part how much the abnormal deformation of the element generated in the tire model 20 can be suppressed by changing the setting of the characteristic parameter of the part. This evaluation is performed by relative evaluation between parts. Further, it is preferable that the influence of the change in the characteristic parameter setting on the abnormal deformation of the element is larger. That is, it is preferable that the abnormal deformation of the element is effectively suppressed by a small setting change.

  The part characteristic parameter is a parameter related to the part characteristic, and is set for each part in the simulation of the tire characteristic. By changing the setting of the characteristic parameter, it is possible to suppress abnormal deformation of the element. The characteristic parameters include, for example, elastic modulus and hourglass parameters.

  Next, the influence exerted on the characteristic value related to the tire characteristic by changing the setting of the characteristic parameter of the part is evaluated (characteristic value sensitivity evaluation step ST42). In other words, it is evaluated how much the characteristic value of the tire characteristic changes by changing the setting of the characteristic parameter of the part. This evaluation is performed by absolute evaluation or relative evaluation between parts. In addition, the smaller the influence of the characteristic parameter setting change on the characteristic value, the better. That is, it is preferable that the characteristic value related to the tire characteristic is difficult to change when the characteristic parameter is changed. The characteristic value related to tire characteristics is, for example, the amount of tire deflection with respect to a load.

  Next, based on the evaluation results acquired in the element deformation evaluation step ST41 and the characteristic value sensitivity evaluation step ST42, there is a part that has a large effect of suppressing abnormal deformation of the element and a small influence on the change in the characteristic value related to the tire characteristics. Selected (part selection step ST43). At this time, the effect of suppressing the abnormal deformation of the element and the magnitude of the influence on the change of the characteristic value are relatively determined between the parts. The selected part may be either a single part or a plurality of parts.

  Next, the characteristic parameter of the selected part is changed (or initially set) so that abnormal deformation of the element is suppressed (parameter setting step ST44). At this time, the characteristic parameter setting change may be performed a plurality of times (repeatedly). Further, when a plurality of parts are selected, the characteristic parameters are set and changed for each selected part.

[effect]
In the tire characteristic simulation device 1, among the plurality of parts constituting the tire model 20, when the setting of the characteristic parameter is changed, the influence on the effect of suppressing abnormal deformation of the element is large, and the characteristic relating to the tire characteristic A part having a small influence on the change in value is selected, and the characteristic parameters of the selected part are adjusted so that abnormal deformation of the element is suppressed. In such a configuration, since it is possible to suppress abnormal deformation of the elements while reducing the influence on the tire characteristic value, it is possible to create a highly accurate tire model. Thereby, there exists an advantage which the prediction precision of a tire characteristic increases.

  Further, in such a configuration, the calculation time required for the simulation is shortened as compared with the configuration in which the number of elements of the tire model 20 is increased (the tire model 20 is subdivided) to suppress abnormal deformation of the elements. There is.

  Further, in such a configuration, compared with a configuration in which the elastic modulus (elastic modulus of the material) given to the entire element of the tire model 20 in the simulation is uniformly increased to suppress abnormal deformation of the element, modeling of tire stiffness is performed. Since the accuracy is high, there is an advantage that the prediction accuracy of the tire characteristics is high.

  In addition, such a configuration has the advantage that the tire characteristic modeling accuracy is high because the tire rigidity modeling accuracy is high compared to the configuration in which countermeasures against abnormal deformation of elements are made by changing the hourglass control format and parameters, etc. There is.

[Modification 1]
As a method of suppressing abnormal deformation (hour glass deformation) of an element, when an hour glass deformation starts to occur, a virtual force (hour glass drag) that suppresses the deformation is generated in the element. There is a way. As a result, abnormal deformation of the element is suppressed, and the numerical calculation in the simulation is stabilized. Examples of such methods include Hallqulst's viscous hourglass control, Flanagan-Belytachko's viscous hourglass control, Flanagan-Belytachko's rigid hourglass control, Belytsoko-Tsay's viscous and rigid hourglass control, The hourglass control by virtual strain of Belytachko-Bindeman is known.

  Here, the tire characteristic simulation device 1 preferably has a configuration in which the evaluation in the element deformation evaluation step ST1 is performed based on the hourglass energy E accumulated in each part. The hour glass energy E is energy accumulated in the analysis target (tire model 20) by the hour glass drag, and the smaller the value, the less the abnormal deformation of the element, which is preferable. Specifically, the characteristic parameters are set and changed for each part, a numerical simulation is performed, and the hourglass energy E is calculated. And relative evaluation between each part is performed based on the calculation result. Thereby, there is an advantage that occurrence of abnormal deformation of the element is appropriately determined.

  In such a configuration, it is preferable that the occurrence of abnormal deformation of the element is determined by comparing the hourglass energy E accumulated in each part with the internal energy U when determining the tire model 20 (ST3). That is, when the hourglass energy E accumulated in the parts exceeds a predetermined ratio with respect to the internal energy U, the analysis accuracy of the tire characteristics deteriorates. Therefore, by comparing the hourglass energy E and the internal energy U, there is an advantage that the occurrence of abnormal deformation of the element can be properly determined.

  For example, when the hour glass energy E of the part and the internal energy U are in a relationship of E ≧ U × 0.10, it is determined that an abnormal deformation of the element has occurred. The hour glass energy E is preferably closer to zero.

[Modification 2]
In the tire characteristic simulation apparatus 1, it is preferable that at least one of the elastic modulus of the part and the hourglass parameter of the part is included in the characteristic parameter of the part. Such a configuration has an advantage that the calculation time required for the simulation is shortened as compared with a configuration in which the number of elements of the tire model 20 is increased to suppress abnormal deformation of the elements.

  In such a configuration, it is preferable that the characteristic parameter (design variable) of the part is selected so that the characteristic value (objective function) related to the tire characteristic is optimized. Thereby, there exists an advantage which the prediction precision of a tire characteristic improves. A technique known to those skilled in the art is employed as the optimization technique.

  FIG. 6 is an explanatory diagram illustrating an example in which optimization is performed using an experiment design method (L16 orthogonal experiment). In this example, a tire having a tire size of 315 / 80R22.5 is used, and an internal pressure of 900 [kPa] is applied to the tire 10. Further, the elastic modulus is set as a characteristic parameter of the seven types of parts of the tire 10. Further, the relationship between the load applied to the tire 10 and the amount of deflection of the tire 10 is simulated and compared with the measured value.

  In this example, the absolute value of the difference between the longitudinal deflection amount with respect to the load and the target value is equal to or less than the threshold ε = 0.1 [mm], and the hour glass energy E and the internal energy U of the part are E ≦ U. Part characteristic parameters (elastic modulus) are selected so as to have a relationship of × 0.10. Then, as compared with the conventional example, it can be seen that the simulation result of the longitudinal deflection amount substantially coincides with the measured value, and the tire characteristics are accurately reproduced (see FIG. 6). The conventional example is an example in which such optimization is not performed.

  In the above configuration, it is preferable that the characteristic value related to the tire characteristic is a tire bending characteristic when a predetermined internal pressure and a predetermined load are applied. In such a configuration, the reproduction accuracy with respect to the contact shape of the tire and the contact pressure distribution is improved. Thereby, there exists an advantage which the prediction precision of a tire characteristic improves. In addition, there is an advantage that the prediction accuracy concerning the motion characteristics and wear characteristics at the time of tire rolling is improved.

  FIG. 7 shows a simulation result and a measurement result of the contact shape of the tire model 20 in which the deflection characteristic is set as an objective function (characteristic value related to the tire characteristic). The load applied to the tire 10 is 40 [kN]. As shown in FIG. 7, it can be seen that the ground contact shape of the tire is accurately reproduced by the above optimization.

[Application example]
The tire characteristic simulation apparatus 1 is preferably applied to a tire tire model 20 to which an internal pressure of 500 [kPa] or more is applied. For example, in a tire in which a high internal pressure is applied at the time of inflation such as a tire for trucks and buses, abnormal deformation of elements is likely to occur in the created tire model 20. Therefore, by using the tire model 20 of the tire 10 as an application target, there is an advantage that the effect of improving the prediction accuracy of the tire characteristics can be favorably obtained.

  As described above, the tire characteristic simulation apparatus and method and the tire model creation method according to the present invention are useful in that the accuracy of prediction of tire characteristics can be improved.

It is a block diagram which shows the simulation apparatus of a tire characteristic. It is a flowchart which shows the simulation method of a tire characteristic. It is a flowchart which shows the simulation method of a tire characteristic. It is sectional drawing which shows an example of a tire. It is a perspective view showing an example of a tire model. It is explanatory drawing which shows an example of an optimization process. It is explanatory drawing which shows an example of an optimization process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tire characteristic simulation apparatus 2 Control apparatus 3 Input apparatus 4 Output apparatus 21 Tire model creation part 22 Simulation part 31 Data input part 32 Test condition input part 10 Tire 11 Bead core 12 Bead filler 13 Carcass layer 14 Belt layer 15 Under tread 16 Cap tread 17 Side tread 20 Tire model

Claims (9)

A tire characteristic simulation device including means for creating a tire model by dividing the shape of a tire composed of a plurality of parts into a plurality of elements, and means for performing a simulation on tire characteristics for the tire model,
An element deformation evaluation means for evaluating for each part the influence on the abnormal deformation of the element by the setting change of the characteristic parameter of the part;
Characteristic value sensitivity evaluation means for evaluating the influence exerted on the characteristic value related to the tire characteristic by the setting change of the characteristic parameter of the part;
Based on the evaluation results acquired by the element deformation evaluation means and the characteristic value sensitivity evaluation means, a part that has a large effect of suppressing abnormal deformation of the element and a small influence on a change in the characteristic value related to tire characteristics is selected. Parts selection means,
A tire characteristic simulation apparatus comprising: parameter setting means for setting characteristic parameters of the selected part so that abnormal deformation of the element is suppressed.   The tire characteristic simulation device according to claim 1, wherein the evaluation in the element deformation evaluation unit is performed based on hourglass energy E accumulated in the part.   The tire characteristic simulation device according to claim 1, wherein occurrence of abnormal deformation of the element is determined by comparing the hourglass energy E and the internal energy U accumulated in the part.   The tire characteristic simulation device according to any one of claims 1 to 3, wherein at least one of an elastic modulus of the part or an hourglass parameter of the part is included in the characteristic parameter.   The tire characteristic simulation device according to any one of claims 1 to 4, wherein the characteristic parameter is selected so that a characteristic value related to tire characteristics is optimized.   6. The tire characteristic simulation apparatus according to claim 5, wherein the characteristic value related to the tire characteristic is a tire bending characteristic when a predetermined internal pressure and a predetermined load are applied, and the characteristic parameter includes an elastic modulus.   The tire characteristic simulation device according to any one of claims 1 to 6, which is applied to a tire model of a tire to which an internal pressure of 500 [kPa] or more is applied. A tire characteristic simulation method including a step of creating a tire model by dividing a tire shape formed of a plurality of parts into a plurality of elements, and a step of performing a simulation related to the tire characteristic for the tire model,
An element deformation evaluation step in which the influence on the abnormal deformation of the element due to the setting change of the characteristic parameter of the part is evaluated for each part;
A characteristic value sensitivity evaluation step in which the influence on the characteristic value related to the tire characteristic by the setting change of the characteristic parameter of the part is evaluated;
Based on the evaluation results obtained by the element deformation evaluation means and the characteristic value sensitivity evaluation means, a part is selected that has a large effect of suppressing abnormal deformation of the element and a small influence on changes in the characteristic values related to tire characteristics. Part selection step,
And a parameter setting step of setting a characteristic parameter of the selected part so that abnormal deformation of the element is suppressed. A tire model creation method for creating a tire model by dividing a tire shape composed of a plurality of parts into a plurality of elements,
An element deformation evaluation step in which the influence on the abnormal deformation of the element due to the setting change of the characteristic parameter of the part is evaluated for each part;
A characteristic value sensitivity evaluation step in which the influence on the characteristic value related to the tire characteristic by the setting change of the characteristic parameter of the part is evaluated;
Based on the evaluation results obtained by the element deformation evaluation means and the characteristic value sensitivity evaluation means, a part is selected that has a large effect of suppressing abnormal deformation of the element and a small influence on changes in the characteristic values related to tire characteristics. Part selection step,
And a parameter setting step of setting a characteristic parameter of the selected part so that abnormal deformation of the element is suppressed.

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