JP2014077759A - Simulation method and simulation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simulation method and a simulation device, in dynamic analysis of a tire model in which a viscoelastic characteristic is defined, that can acquire a value of energy loss of the tire for accurately evaluating performance of the tire while suppressing a rotation frequency.SOLUTION: A simulation method includes: a step A of generating a tire model including predetermined elements in which a viscoelastic characteristic is defined; a step B of generating a road surface model; a step C of rolling the tire model on the road surface model, and subtracting an elastic strain energy change quantity ΔWgiven to the predetermined elements from a work change quantity ΔW given to the predetermined elements for each micro time during rolling motion, to acquire history data of dissipation energy density ΔW1generated in the predetermined elements; and a step D of, on the basis of the history data corresponding to the predetermined elements included in a partial model of the tire model and a rolling period in which the tire model has rolled predetermined times, acquiring partial dissipation energy ΔW2generated in the partial model during the rolling period.

Description

  The present invention relates to a tire simulation method and a simulation apparatus.

  In order to improve the efficiency of the development of a pneumatic tire (hereinafter referred to as a tire), simulation using a numerical analysis method such as a finite element method is effective. It is possible to predict tire performance due to energy loss by a simulation method using a tire model including an element in which viscoelastic characteristics are defined (see, for example, Patent Document 1).

  In the simulation method according to Patent Document 2, a tire model is set by dividing a tire by a finite number of elements including elements having viscoelastic characteristics defined, and the tire model is rolled on a road surface model. The longitudinal force of the axle resulting from the energy loss generated in the model is acquired, and the rolling resistance of the tire is calculated from the longitudinal force of the axle.

  According to such a simulation method, since it is possible to perform dynamic viscoelasticity analysis using a tire model including elements having viscoelastic characteristics defined, it is possible to improve the accuracy of predicting and evaluating tire performance. It becomes possible.

JP 2007-131209 A

  In the simulation method according to the prior art, when the tire performance based on the energy loss is evaluated in the dynamic analysis of the tire model in which the viscoelastic property is defined, the energy loss of the element acquired under the condition where the rotational speed is different is included. Therefore, there are cases where the evaluation value for accurately evaluating the tire performance is not appropriate.

  Therefore, the present invention has been made in view of the above-described problems, and in the dynamic analysis of a tire model in which viscoelastic characteristics are defined, for accurately evaluating the tire performance while suppressing the rotational speed. It is an object of the present invention to provide a simulation method and a simulation apparatus capable of obtaining energy loss.

A first feature of the present invention is a simulation method using a tire model generated by dividing a tire into a finite number of elements, and includes a predetermined number of elements including viscoelastic characteristics defined in the finite number of elements. By dividing, step A (step S101) for generating the tire model, step B (step S101) for generating a road surface model, rolling the tire model on the road surface model, and rolling By subtracting the elastic strain energy change amount ΔW ^e applied to the predetermined element from the work change amount ΔW applied to the predetermined element every minute time, the dissipated energy density ΔW1 ^v generated in the predetermined element Step C (step S102) for obtaining history data indicating the history of the tire, and a partial model that is a part of the tire model A step D () for obtaining a partial dispersion energy ΔW2 ^ν generated in the partial model within the rotation period based on the history data corresponding to the predetermined element included in the loop and the rotation period rolled a predetermined number of times. Step S103) is included.

In such a simulation method, the partial dispersion energy ΔW2 ^ν generated in the partial model that is a part of the tire model is acquired as an energy loss. Therefore, in the energy loss acquired by the dynamic viscoelastic analysis, the rotational speed is the same as in the prior art. It is possible to prevent energy loss of elements obtained under different conditions. Also, in this simulation method, the rotational speed is common and the energy loss of the elements used for steady-state tire performance can be acquired without increasing the rotational speed as compared with the prior art.

That is, according to such a simulation method, energy loss of an element under a condition where the rotational speed is common can be acquired more appropriately while suppressing the rotational speed, so that energy capable of more accurately evaluating the tire performance can be obtained. Loss can be acquired. The partial dispersion energy ΔW2 ^ν of the partial model acquired in this way can be used for tire performance analysis such as energy loss distribution in the tire model. It is desirable that the partial dispersion energy ΔW2 ^ν be divided into predetermined elements or groups of predetermined rubber materials in the partial model. The reason for this is that, by doing so, it becomes possible to know which part contributes greatly in the evaluation of the dissipated energy distribution, and a guideline for tire improvement can be obtained.

Another feature of the present invention, obtains the ratio of the partial model for the tire model, on the basis of said partial energy dissipated Derutadaburyu2 ^[nu, the entire dissipated energy Derutadaburyu3 ^[nu of the tire model corresponding to the partial dissipated energy Derutadaburyu2 ^[nu The gist is to further include step E (step S104). The gist of the present invention is that it further includes a step F (step S105) of performing a rolling resistance analysis based on the total dissipated energy ΔW3 ^ν .

Another feature of the present invention relates to the above feature, and is summarized in that the rotation period is a period of the last one rotation during rolling. Another feature of the present invention relates to the above feature, and further includes a step of performing a temperature analysis based on at least one of the history data indicating the history of the dissipation energy density ΔW1 ^ν or the partial dispersion energy ΔW2 ^ν . This is the gist.

  According to the present invention, in a dynamic analysis of a tire model in which viscoelastic characteristics are defined, a simulation method and simulation capable of obtaining energy loss for more accurately evaluating tire performance while suppressing the rotational speed An apparatus can be provided.

FIG. 1 is a flowchart showing a simulation method according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing an example of a tire model to be analyzed used in the simulation method according to the embodiment of the present invention. FIG. 3 is a perspective view showing an example of a tire model to be analyzed and a road surface model used in the simulation method according to the embodiment of the present invention. FIG. 4 is an explanatory diagram illustrating an example of a cross-sectional model in which the angle θ is part of the tire circumferential direction with the axial center of the tire model according to the embodiment of the present invention as a base point. FIG. 5A is a graph showing an integrated value (cumulative value) of partial dispersion energy ΔW2 ^v generated in the cross-sectional model from the start to the end of rolling of the tire model. FIG. 5B is a graph showing an integrated value (cumulative value) of dissipated energy generated in the entire tire model.

  Embodiments of the present invention will be described with reference to the drawings. Hereinafter, in the drawings in each embodiment, the same or similar parts are denoted by the same or similar reference numerals. However, the drawings are schematic, and the ratio of each dimension is different from the actual one. Moreover, the part from which the relationship and ratio of a mutual dimension differ also in between drawings is contained.

[First Embodiment]
The simulation method according to the first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a flowchart of the simulation method according to the first embodiment of the present invention.

  As shown in FIG. 1, in step S101, the tire model 100 is generated by dividing into a finite number of elements including a predetermined element in which viscoelastic characteristics are defined. A tire model including a finite number of elements is generated by performing element division (that is, mesh division) corresponding to the finite element method on the tire to be analyzed. FIG. 2 shows a cross-sectional view in the tread width direction (X-axis direction) of the tire to be analyzed, and FIG. 3 shows a perspective view of the tire model 100 to be analyzed. The tire model 100 is digitized into a format that can be handled by a computer device. The tire to be analyzed may be a newly designed tire or an existing tire.

  Here, when generating the tire model 100 described above (that is, when dividing the mesh), the skeleton member or the reinforcing member of the tire to be analyzed is defined as any element of a membrane element, a shell element, or a solid element. .

  Next, the design information of the tire to be analyzed is input. Specifically, viscoelastic properties are defined for the elements. Here, various methods can be applied as a method for specifying the input viscoelastic characteristics. For example, as disclosed in Japanese Patent Application Laid-Open No. 2007-131209, a method of acquiring a strain amount and a frequency of the tire model 100 and specifying a viscoelastic constant of rubber as a viscoelastic characteristic based on the acquisition result. Etc. can be applied. Further, when defining the viscoelastic characteristics, the viscoelastic constant of each rubber of each tire material is specified as the viscoelastic characteristics, and the viscoelastic characteristics are defined for elements corresponding to the respective portions.

  Moreover, the tire model 100 is produced | generated by expand | deploying the cross-sectional model produced | generated in this way for the tire circumference. In consideration of modeling such as a tread pattern, the method is not particularly limited to a method in which a cross-sectional model is developed around the tire.

  Subsequently, as shown in FIG. 2, a road surface model 200 is generated. As shown in FIG. 3, the road surface model 200 can be modeled by a flat rigid shell element, or actual road surface unevenness can be modeled. On the other hand, in order to accurately estimate the rolling resistance value measured on the drum, a drum model 200A obtained by modeling a drum used in a tire rolling test can be used as a road surface model.

  In step S102, the tire model 100 is brought into contact with the road surface model 200 and the tire model 100 is rolled. That is, in step S102, viscoelastic rolling analysis is executed. Here, as a method of rolling the tire model 100, boundary conditions are set so that the tire model 100 rotates around the axle, a model is created, and either the road surface model 200 or the axle is fixed, Analysis can be made by moving the other side in the longitudinal direction of the tire.

  Furthermore, it is possible to give a slip angle or a camber angle to the tire model 100, and it is also possible to move the road surface model 200 so that the tire model 100 has a slip angle or a camber angle. In this way, a simulation of rolling the tire model 100 at least one turn or more is performed.

In addition, the dissipated energy generated in the predetermined element by subtracting the elastic strain energy change amount ΔW ^e applied to the predetermined element from the work change amount ΔW applied to the predetermined element for each minute time Δt during rolling. History data indicating the history of density ΔW1 ^ν is acquired. The predetermined element is a rubber element in which viscoelastic properties are defined, and will be described below simply as an element.

Specifically, the elastic strain applied to each element is acquired in a minute time Δt during rolling. Based on this elastic strain, an elastic strain energy change amount ΔW ^e given to each element is calculated. Further, the work change amount ΔW given to each element is calculated based on the total strain and stress given to each element.

  Here, the minute time Δt is preferably defined as a time (period) in which the distortion waveform (distortion change) can be analyzed more accurately, and is preferably as short as possible, but is calculated as the value of the minute time Δt is small. The time will be longer. Therefore, the values determined by the following formula (1) are calculated based on the size and the speed (sound speed) at which the elastic wave is transmitted for all elements, and the minimum value among them is set as the upper limit value, and 10% of the upper limit value. Is preferably defined as the lower limit.

Δt = minimum value of the length of one side of the element / sound speed (1)

Further, the work change amount ΔW can be calculated using the following mathematical formula (2) based on the stress σ and the strain increment Δε in the element which is the tensor amount on the second floor. In Equation (2), the suffix “T” at the upper right of the stress symbol represents the transposition of the tensor.

ΔW = σ ^T : Δε (2)

On the other hand, as the difference of the elastic strain energy change amount [Delta] W ^e, the elastic strain energy W ^e at time t defined by the strain in the elastic portion of the material model defined in a predetermined element, the elastic strain energy W ^e at time t + Delta] t, It can be calculated using the following mathematical formula (3).

ΔW ^e = W ^e (t + Δt) −W ^e (t) (3)

In the above equation (3), the elastic strain energy W ^e can be calculated using any one of the following formulas (4) to (6). Specifically, the elastic strain energy W ^e, based on one or more elastic portions having the material model, calculated using any one of the following formulas (4) to (6), by adding them Ask. Here, the material model having an inelastic portion and an elastic portion includes, for example, the Kelvin-Voigt model, the Maxwell model, the generalized Maxwell model, and the like, as well as Non-Patent Document 1 (“Rubber Superelasticity—Viscoplasticity—Damage Model ”, Rubber engineering super-elasticity-viscoplasticity-damage model, etc., as described in the Proceedings of the Computational Engineering Lecture, Vol.12, pp. 333-336, 2007) It is not limited. The elastic portion generally indicates a portion indicated by a spring element in the material model, and the non-elastic portion generally indicates a portion indicated by a dash pod in the material model. The inelastic portion is not limited to viscosity, and may include plasticity, damage, and the like.

W ^e (t) = (ε ^e (t) ^T : C: ε ^e (t)) / 2 (4)
ε ^e : Elastic part strain (2nd floor tensor), C: Elastic coefficient matrix (4th floor tensor)

W ^e (t) = W ^e (λ ₁ (t), λ ₂ (t), λ ₃ (t)) (5)
λ _i : Elastic part elongation ratio

W ^e (t) = W ^e (I ₁ (t), I ₂ (t), I ₃ (t)) (6)
I _i : Invariant of the right Cauchy green tensor of the elastic part

For example, when the element is a linear elastic body, Formula (4) can be used. When the element is a superelastic body, Equation (5) that is an Ogden model, Equation (6) that is a Neo-Hookan model, or a Moony-Rivlin model can be used. As the mathematical formulas of these models, the optimal mathematical formulas for the elements of the respective members may be applied according to the material characteristics of the respective members constituting the tire.

History data in which the dissipated energy density ΔW1 ^{ν for} each minute time Δt calculated in this way is associated with time data is generated for each predetermined element included in the tire model 100. The dissipated energy density ΔW1 ^ν can be restated as an energy loss density for each minute time Δt.

The history data may include time data and the dissipated energy density ΔW1 ^{ν for} each minute time Δt associated with the time data, or the time data and the minute data associated with the time data. An integrated value of the dissipated energy density ΔW1 ^ν for each time Δt (an integrated value with an initial value of “0”) may be included. In the history data according to the present embodiment, as in the latter case, the integrated value (initial value is “0”) of the time data and the dissipated energy density ΔW1 ^ν for each minute time Δt associated with the time data. Integrated value).

In step S103, based on the history data corresponding to the predetermined element included in the cross-sectional model 110 that is a part of the tire model 100 and the rotational period Tr that has been rolled a predetermined number of times, the cross-sectional model 110 within the rotational period Tr The generated partial dispersion energy ΔW2 ^ν is acquired.

  Here, in FIG. 4, a cross-sectional model 110 in which an element corresponding to an angle θ of 1 degree is a part in the tire circumferential direction when the entire circumference of the tire is 360 degrees with the axial center C of the tire model 100 as a base point. An example is shown. Note that the configuration of the cross-sectional model 110 is not limited to this, and may be a cross-sectional model 110 in which more angles θ (for example, 5 degrees) are part of the tire circumferential direction. The cross-sectional model 110 may be one in which one element in the tire circumferential direction is a part in the tire circumferential direction.

  Furthermore, based on the tread pattern, the cross-sectional model 110 may be a part of one pitch in the tire circumferential direction, and width direction grooves extending in the tread width direction are formed at predetermined intervals in the tire circumferential direction. In some cases, the cross-sectional model 110 may be a set of one block partitioned by the width direction groove and one width direction groove (one pitch) as a part in the tire circumferential direction. In the present embodiment, the cross-sectional model 110 constitutes a partial model that is a part of the tire model 100.

A predetermined element included in the cross-sectional model 110 defined in this way is specified, and history data of the dissipation energy density ΔW1 ^ν corresponding to the predetermined element is specified. In general, the cross-sectional model 110 includes a plurality of predetermined elements. In such a case, a plurality of history data corresponding to each of a plurality of predetermined elements is specified.

Further, in the history data, with reference to the dissipated energy density .DELTA.W1 ^[nu associated with time data, cross-sectional model 110 the dissipated energy density .DELTA.W1 ^[nu obtained in a rotating period tr rolling predetermined number of times during rolling Identify. Further, based on the specified dissipated energy density ΔW1 ^ν , the partial dispersion dissipated energy ΔW2 ^ν generated in the cross-sectional model 110 within the rotation period tr is acquired. In the present embodiment, details will be described below by taking a case where the predetermined number of times is one rotation as an example.

Here, FIG. 5A shows a graph of the integrated value (cumulative value) of the dissipated energy density ΔW1 ^ν generated in the cross-sectional model 110 from the start of rolling of the tire model 100 to the end of rolling. ing. In other words, the graph shown in FIG. 5A is a total value obtained by adding up the integrated values of the dissipated energy densities ΔW1 ^ν corresponding to all the predetermined elements included in the cross-sectional model 110 (hereinafter referred to as an integrated total value). It can be rephrased as a graph indicating a value in which the time data is associated with the time data.

Further, the integrated value of the dissipative energy density ΔW1 ^ν increases stepwise along the time axis direction as shown in FIG. This is because the dissipated energy density ΔW1 ^ν generated during rolling increases during the ground contact period of the cross-sectional model 110, but does not increase much during periods other than the ground contact period.

As shown in FIG. 5 (a), from the accumulated total value of the dissipated energy density .DELTA.W1 ^[nu occurring predetermined elements included in the cross-sectional model 110, dissipated energy density in the rotation period tr per revolution is a predetermined period .DELTA.W1 ^[nu Is obtained as partial dispersion energy ΔW2 ^ν .

For example, as shown in FIG. 5A, the start time A and the end time B of the rotation period tr in the fourth rotation are specified. Further, by subtracting the integrated total value of the dissipated energy density ΔW1 ^{ν at} the start time A from the integrated total value of the dissipated energy density ΔW1 ^{ν at} the end time B, it is possible to obtain the partial dispersion energy ΔW2 ^ν .

The method for obtaining the partial dispersion energy ΔW2 ^ν is not limited to this. For example, for each predetermined element included in the cross-sectional model 110, from the integrated value of the dissipated energy density .DELTA.W1 ^[nu at the end time B, and subtracts the integrated value of dissipated energy density .DELTA.W1 ^[nu at the start time A. Then, by adding the subtraction results for each predetermined element included in the cross-sectional model 110, the partial dispersion energy ΔW2 ^ν can be calculated.

Further, when the dissipated energy density ΔW1 ^ν included in the history data is not an integrated value but simply a dissipated energy density ΔW1 ^ν generated in a predetermined element per minute time Δt, the partial dispersion dissipated energy ΔW2 ^ν may be calculated. Is possible. Specifically, the dissipative energy density ΔW1 ^ν generated in the predetermined element per minute time Δt is time-integrated by the rotation period Tr per one rotation that is a predetermined period. Then, by adding the time integration results for each predetermined element included in the cross-sectional model 110, the partial dispersion energy ΔW2 ^ν can be calculated.

  Further, the rotation period tr is preferably a period of the last one rotation while the tire model 100 is rolling. Here, FIG. 5B is a graph showing an integrated value (cumulative value) of dissipated energy generated in the entire tire model 100. During the rolling of the tire model 100, the dissipated energy generated in the entire tire model 100 becomes a steady state that shows a monotonous increasing tendency close to a straight line as time passes, that is, as the number of rolling increases. This is because the dissipated energy (energy loss) changes due to the influence of the material characteristics defined in the elements included in the tire model 100, but the amount of change in the dissipated energy increment decreases as the number of rolling increases. It is shown that.

  Accordingly, the rotation period tr becomes closer to the steady state as the period after the tire model 100 is rolled for dynamic viscoelasticity analysis (the subsequent one rotation) is closer to the steady state. A small and stable dissipative energy can be obtained, which is preferable. Furthermore, the rotation period tr is more preferably the last one rotation period.

In step S104, it obtains the ratio of the cross-sectional model 110 with respect to the tire model 100, based on the partial energy dissipated Derutadaburyu2 ^[nu, the entire tire model 100 corresponding to the portion dissipated energy Derutadaburyu2 ^[nu across dissipated energy ΔW3 ^ν. Specifically, the total dissipated energy ΔW3 ^ν in the entire tire model 100 is obtained by integrating the partial dispersion energy ΔW2 ^ν according to the ratio of the volume of the cross-sectional model 110 to the volume of the tire model 100.

For example, in the present embodiment, the cross-sectional model 110 is in the range of 1/360 degrees in the tire circumferential direction of the entire tire model 100, and therefore, by multiplying the partial dispersion energy ΔW2 ^ν by 360, The total dissipated energy ΔW3 ^ν can be acquired.

In step S105, tire performance is analyzed using the total dissipated energy ΔW3 ^ν . That is, an analysis for evaluating tire performance is performed. Specifically, a rolling resistance analysis can be performed using the total dissipation energy ΔW3 ^ν .

As a method of performing the rolling resistance analysis using the total dissipation energy ΔW3 ^ν , for example, if the rolling resistance is calculated by dividing the total dissipation energy ΔW3 ^ν by the length of one round of the tire, the rolling resistance analysis is performed. be able to.

Moreover, since dissipated energy is a heat source, it can be applied to temperature analysis. As a method of performing temperature analysis, the dissipative energy ΔW1 ^ν of each partial element is used as a heat source, the dissipative energy density ΔW1 ^ν , the volume of the tire model 100, and the material characteristics of the elements in the tire model 100 (specific heat, thermal conductivity). Etc.), the steady-state temperature distribution in the tire model 100 can be analyzed. Further, the dissipative energy density ΔW1 ^ν is a heat source, and comparison with other elements in the cross section compares contributions to the tire dissipative energy, and is important for obtaining an idea of performance improvement.

Furthermore, the temperature analysis can be performed based on the partial dispersion energy ΔW2 ^ν without being limited to the dissipation energy ΔW1 ^ν . Specifically, the steady temperature distribution in the tire model 100 can be analyzed based on the partial dispersion energy ΔW2 ^ν and the material characteristics (specific heat, thermal conductivity, etc.) of the elements in the tire model 100.

  In the simulation method according to the above-described embodiment, the case where the operation of Step S102 is executed as the dynamic viscoelasticity analysis and the operation of Steps S103 to S105 is executed as post-processing has been described. As the elastic analysis, the operations in steps S102 to S105 may be executed. That is, operations 102 to 105 may be executed while rolling the tire model 100.

(Function and effect)
In the simulation method according to the present embodiment, since the partial dispersion energy ΔW2 ^ν generated in the cross-sectional model 110 is acquired as an energy loss, the energy loss of the elements acquired under conditions with different rotational speeds as in the prior art is included. Can be prevented.

  Further, in the simulation method according to the present embodiment, the rotational speed is common and the energy loss of the elements used for the evaluation of the tire performance can be acquired without increasing the rotational speed as compared with the conventional technique.

That is, according to the simulation method according to the present embodiment, it is possible to more appropriately acquire the energy loss of the element under the condition where the rotational speed is common while suppressing the rotational speed, and thus it is possible to more accurately evaluate the tire performance. Can obtain possible energy loss. The partial dispersion energy ΔW2 ^ν of the cross-sectional model 110 acquired in this way is a part of the tire model 100, but can be used for tire performance analysis such as energy loss distribution.

In the simulation method according to the present embodiment, the overall dissipated energy ΔW3 ^ν in the entire tire model 100 is acquired based on the ratio of the cross-sectional model 110 to the tire model 100. That is, since it is possible to obtain the overall dissipated energy ΔW3 ^ν of the entire tire model 100 configured by elements having a common rotational speed, it is possible to more accurately evaluate tire performance based on energy loss. become.

Further, according to the simulation method according to the present embodiment, the entire dissipated energy ΔW3 ^ν of the entire tire model 100 configured by elements having a common rotational speed is used as the energy loss. Evaluation can be performed more accurately.

[Comparison evaluation]
Next, in order to further clarify the effects of the present invention, a comparative evaluation test performed using the simulation method according to the conventional example and the simulation methods according to Examples 1 to 3 will be described. In addition, this invention is not limited at all by these examples.

  In this test, a tire with a tire size of “195 / 65R15” was mounted on a drum having a diameter of 1.7 m with a rim of 6.0JJ, an internal pressure of 210 kPa, and a vertical load of 4 kN. The rolling resistance was measured when rolling at 80 KPH. Moreover, under the same conditions as those at the time of actual measurement, the predicted values of the rolling resistance calculated using the conventional example, the comparative example, and the simulation method according to the example of the present invention were compared.

  In the simulation method according to the conventional example, the predicted value of the rolling resistance is calculated by post-processing using the loss tangent based on the amount of strain obtained by the elastic analysis.

  In the simulation method according to Comparative Example 1, road tangential force is obtained by performing dynamic viscoelasticity analysis, and this road surface tangential force is used as a predicted value of rolling resistance.

In the simulation method according to the first embodiment, by performing dynamic viscoelastic analysis, the dissipated energy of the entire tire model (total dissipated energy ΔW3 ^ν ) is acquired, and the predicted value of the rolling resistance is calculated based on this dissipated energy. Was calculated. In the simulation method according to Example 1, the dissipated energy (partial dissipated energy ΔW2 ^ν and total dissipated energy ΔW3 ^ν ) was acquired based on the rotation period tr of the fifth rotation of the tire.

  The simulation method according to the second embodiment is the same as the simulation method according to the first embodiment except that the number of rolling is based on the rotation period tr of the second rotation.

Table 1 below shows predicted values of rolling resistance in the simulation methods according to the conventional example, the comparative example 1, and the examples 1 and 2. The predicted value is indicated by an index with the actually measured value as a reference (100).

As shown in Table 1, the simulation method according to Examples 1 and 2 corresponding to the simulation method of the present invention showed a clear advantage over the conventional example and the comparative example.

  Further, comparing Example 1 and Example 2, compared to Example 2 in which the number of rolling is based on the second rotation period Tr, Example 1 in which the number of rolling is based on the fifth rotation period Tr. Was shown to be superior. That is, it was proved that the more accurate the dissipated energy can be acquired as the energy loss as the rotation period tr is a period of one rotation after the tire model 100 is rolling.

[Other Embodiments]
As mentioned above, although this invention was demonstrated in detail using the above-mentioned embodiment, this invention is not limited to embodiment described in this specification. For example, in the above-described embodiment, the period per one rotation of the tire rolling is set as the rotation period tr, and the dissipation energy (partial dispersion energy ΔW2 ^ν and total dissipation energy ΔW3 ^ν ) is acquired. The period per two rotations may be the rotation period tr.

  Further, the above-described embodiment and modification examples can be combined. As described above, the present invention can be implemented as modifications and changes without departing from the spirit and scope of the present invention defined by the description of the scope of claims. Therefore, the description of the present specification is for illustrative purposes and does not have any limiting meaning to the present invention.

  DESCRIPTION OF SYMBOLS 10 ... Belt reinforcement layer, 20A, 20B ... Inclined belt layer, 30 ... Carcass ply layer, 100 ... Tire model, 110 ... Section model, 200 ... Road surface model, 200A ... Drum model

Claims (6)

A simulation method using a tire model generated by dividing a tire into a finite number of elements,
Generating the tire model by dividing it into a finite number of elements including predetermined elements having viscoelastic properties defined;
Generating a road surface model B;
The tire model is rolled on the road surface model, and the elastic strain energy change amount ΔW applied to the predetermined element from the work change amount ΔW applied to the predetermined element for each minute time during rolling. obtaining history data indicating the history of the dissipated energy density ΔW1 ^ν generated in the predetermined element by subtracting ^e ; and
Based on the history data corresponding to the predetermined element included in the partial model that is a part of the tire model and the rotation period that has been rolled a predetermined number of times, the partial dispersion generated in the partial model within the rotation period And a step D of obtaining energy ΔW2 ^ν . The ratio of the partial model for the tire model, on the basis of said partial energy dissipated Derutadaburyu2 ^[nu, further comprising the step E of obtaining a total dissipated energy Derutadaburyu3 ^[nu of the tire model corresponding to the partial dissipated energy Derutadaburyu2 ^[nu The simulation method according to claim 1, wherein: The simulation method according to claim 2, further comprising a step of performing a rolling resistance analysis based on the total dissipation energy ΔW3 ^ν . The simulation method according to any one of claims 1 to 3, wherein the rotation period is a period of one last rotation during rolling. The simulation method according to claim 1, further comprising a step of performing a temperature analysis based on at least one of the history data indicating the history of the dissipation energy density ΔW1 ^ν or the partial dispersion energy ΔW2 ^ν . . A simulation apparatus that executes the simulation method according to claim 1.

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