JP2004093530A - Dynamic characteristics simulation method of composite material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To highly accurately simulate dynamic characteristics of a composite material in a short time, when the dynamic characteristics of the composite material embedded in a structure and having a wire and a matrix surrounding the wire is simulated. <P>SOLUTION: The dynamic characteristics of the composite material is simulated by a total analysis step of preparing a composite material model made, by discretizing the composite material as a uniform member by finite elements, without discriminating the wire and the matrix in the material and subjecting, to an finite element analysis; the whole structure including the material by representing a material parameter of the material as an equivalent parameter, assuming the material is the uniform member; and a partial analysis step of preparing a matrix model and a wire model formed by discretizing the matrix and the wire by finite elements and subjecting, to a finite element analysis, the dynamic characteristics of the material, on the basis of information which is the result of the finite element analysis obtained by the total analysis step. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention has a wire and a base material surrounding the wire, and has mechanical properties of a composite embedded in a structure, for example, an annular composite such as a hose, a plate composite such as a conveyor belt, and a fender. Simulation of the mechanical properties of composite materials in industrial products such as thin composites, etc., and the mechanical properties of composite materials such as reinforcing materials for pneumatic tires using steel cords as wires and rubber members surrounding the wires as a base material About the method.
[0002]
[Prior art]
Today, pneumatic tires (hereinafter referred to as tires) in which a belt, a carcass or a bead is buried as a reinforcing material have been developed so that these reinforcing materials can be used for a long time without breaking and have excellent durability. .
For example, in the development stage of a tire, in order to check whether a tire having a predetermined design specification has durability, a tire having a predetermined design specification is actually manufactured and a drum test is performed to confirm durability. Alternatively, by using finite element analysis, the tire model is mounted on the rim model, filled with internal pressure, grounded on the road surface, and rotated as necessary to analyze the mechanical characteristics of the tire with predetermined design specifications Simulate and check whether the durability is secured.
In particular, a method of examining tire durability using finite element analysis is an effective method because a finite element model of a tire having desired design specifications can be created without actually producing a tire.
[0003]
On the other hand, a wire, such as a belt, a carcass, or a bead, provided with a steel cord or the like in a tire functions as a reinforcing material for the tire, and is therefore an important member for checking durability. Therefore, it is important to evaluate the mechanical characteristics of a tire reinforcing material having a wire in a belt, carcass, bead, or the like.
By the way, these wires are formed by twisting a plurality of strands, and have a three-dimensionally complicated spiral structure. In order to accurately simulate the mechanical characteristics of the reinforcing material having such a spiral structure, it is necessary to accurately model the configuration of the wire rod in which the strands are twisted three-dimensionally and create a fine model.
[0004]
[Problems to be solved by the invention]
However, since a wire material in a belt, a carcass, a bead, or the like is embedded in the entire tire, it is extremely complicated to create a model of the entire tire incorporating a model of a three-dimensionally twisted spiral wire material. It is an operation, and the time for creating a model is extremely increased. For this reason, there is a problem that it is difficult to quickly analyze the mechanical characteristics by the finite element analysis to check the durability.
Even if an accurate model of the entire tire can be created, there is a problem that the number of model elements and the number of nodes of the entire tire model are extremely increased, and the analysis time by a computer is extremely increased.
[0005]
Such a problem is caused not only by the tires, but also by the industrial use of an annular composite such as a hose, a plate-like composite such as a belt, and a thin composite such as a fender having a wire and a base material surrounding the wire. A similar problem arises when simulating the mechanical properties of a composite material embedded in a structure such as a product or a building.
[0006]
Therefore, the present invention is a method for simulating the mechanical characteristics of a composite material embedded in a structure having a wire and a base material surrounding the wire, and the mechanical characteristics of the composite material can be accurately determined in a short time. It is an object to provide a simulation method for simulating.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention has a wire and a base material surrounding the wire, a method for simulating the mechanical properties of a composite material embedded in a structure,
While creating a composite material model in which the composite material is discretized by finite elements as a uniform member without distinguishing the wire and the base material, material parameters of the composite material having the wire and the base material Expressed by an equivalent parameter as a uniform member, an overall analysis step of performing a finite element analysis of the entire structure including the composite material,
A wire model and a base material model are created by discretizing each of the wire and the base material with a finite element, and based on information on a result of the finite element analysis obtained in the overall analysis step, mechanical properties of the composite material And a method for simulating the mechanical properties of a composite material, the method comprising:
[0008]
At this time, in the partial analysis step, a finite element analysis is performed a plurality of times, and as the number of finite element analyzes increases, a wire model and a wire model in which the configuration of the composite material is reproduced in more detail and discretized by finite elements In the first finite element analysis, a finite element analysis of the mechanical properties of the composite material is performed using information on the result of the finite element analysis obtained in the overall analysis step. In the second and subsequent finite element analyses, it is preferable to perform a finite element analysis of the mechanical properties of the composite material using information on the result of the finite element analysis performed one time before the analysis. For example, when the wire in the composite material is constituted by a plurality of strands, or when the composite material constitutes a textile by the plurality of wires, in the partial analysis step, a plurality of finite element analyzes are performed. It is preferable to perform the finite element analysis by reproducing the configuration of the composite material in more detail as the number of the finite element analysis increases.
[0009]
Further, when the wire model is a model including the end of the wire, in the thickness direction of the composite, a region of 5 times or more the thickness of the composite including the composite is used as the model of the composite. It is preferable to model.
The structure is, for example, a tire including at least one of a twisted cord and a textile cord as the wire, and a rubber member as the base material.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a method for simulating mechanical properties of a composite material according to the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.
[0011]
FIG. 1A shows an apparatus (hereinafter, referred to as an apparatus) 10 for simulating a mechanical property of a tire reinforcing material for executing the method for simulating a mechanical property of a composite material according to the present invention.
[0012]
The apparatus 10 includes a CPU 10a that performs an arithmetic process for creating a model in the finite element method or an arithmetic process of a finite element analysis, a ROM 10b that stores the procedure of the arithmetic process in the CPU 10a, and a partial procedure of the arithmetic process in the CPU 10a. It mainly has a RAM 10c that stores a program that is temporarily stored, and that stores a calculation result processed by the CPU 10a and that is called up as necessary. The device 10 is further connected to a keyboard 12 and a mouse 14 as operation systems via a bus line 10d, and to a display 16 and a printer 18.
The keyboard 12 and the mouse 14 are used to instruct creation of a model by the finite element method and to set analysis conditions for finite element analysis.
The display 16 and the printer 18 are used to display a model to be created and to display a result of the finite element analysis.
Although not shown, it is connected to a storage device such as a hard disk via a bus line 10d.
[0013]
FIG. 1B functionally shows an apparatus 10 having the configuration shown in FIG.
The apparatus 10 includes a model creation unit 20 that creates a model in the finite element method in accordance with the content of an instruction input by the operation system of the keyboard 12 and the mouse 14, and an analysis unit that performs finite element analysis using the created model. 22 and a memory 24 for storing and holding analysis results.
The device 10 is configured as described above.
[0014]
FIG. 2 is a flowchart showing a flow of a method for simulating the mechanical characteristics of a tire reinforcing material executed by such an apparatus 10.
As shown in FIG. 2, the method for simulating the mechanical characteristics of a tire reinforcing material is to create a finite element model and perform a finite element analysis.
[0015]
As is well known, a finite element model is obtained by dividing a structure or the like to be analyzed into a large number of regions by using elements of a finite size called finite elements. The mesh is divided, the nodes in each mesh are represented by three-dimensional coordinate values (or two-dimensional coordinate values), the finite elements and the nodes in the finite elements are numbered, the nodes belonging to each finite element are grouped, and the number of each finite element is grouped. And the number of the nodes as a set.
Therefore, in the finite element model, a set of the number of the node and the coordinate value corresponding to the number, and the number of the finite element and the number of the node in the finite element are stored in an electronic file as model information. Furthermore, information on material parameters (Young's modulus, shear rigidity and Poisson's ratio) corresponding to each finite element is added to the electronic file as material information so that this finite element model is used for finite element analysis.
[0016]
In the flow shown in FIG. 2, first, an entire tire model, which is a finite element model, is created (step 100).
Here, a portion composed of a rubber member such as a tread, a side and a bead, and a portion of a reinforcing material which is a composite material composed of a wire member such as a belt, a carcass and a bead, and a rubber member surrounding the wire member are solid elements. , A whole tire model is created. That is, the model of the reinforcing member portion is discretized by a solid element as one uniform reinforcing member without distinguishing the wire in the reinforcing member and the rubber material surrounding the wire.
[0017]
FIG. 3A shows a partial perspective view of an example of the created whole tire model, and FIG. 3B shows a partial cross-sectional view of the whole tire model 30. The tire models shown in FIGS. 3A and 3B are truck and bus tire models.
As shown in FIG. 3A, the entire tire model 30 is a three-dimensional model, and is mesh-divided at irregular intervals in the tire circumferential direction. This is because, as will be described later, a finite element analysis using the entire tire model 30 is performed with high accuracy by finely dividing a portion that comes into contact with the road surface. In the present invention, the mesh may be divided at equal intervals in the tire circumferential direction.
[0018]
As shown in FIG. 3 (b), the carcass model 32, which is a composite material model according to the present invention, is a discrete reinforcing element made of solid elements as a uniform reinforcing material without discriminating between a wire and a rubber material surrounding the wire. Has been
The solid element is, for example, a tetrahedral solid element, a pentahedral solid element, or a hexahedral solid element.
[0019]
In the examples shown in FIGS. 3A and 3B, three-dimensional solid elements are used. However, a two-dimensional model obtained by dividing a cross-sectional shape as shown in FIG. When performing element analysis, processing may be performed to perform three-dimensional analysis. In this case, a triangular solid element or a quadrangular solid element is used as the solid element.
[0020]
Further, the reinforcing material including a wire such as a belt, a carcass and a bead has a material parameter (Young's modulus, shear stiffness and Poisson's ratio) which is equivalent to a uniform material without distinguishing the wire from a rubber member. Expressed as material parameters of the reinforcing material. Here, the equivalent parameter is obtained by calculating a rigidity constant (Young's modulus, shear rigidity) and a Poisson's ratio of a composite material in which a wire is embedded in a base material at regular intervals using classical lamination theory. Therefore, the material parameters of the reinforcing member are determined by the number of wires, the rigidity of the wire, the rigidity of the rubber material, and the like.
The material information of the material parameters of the reinforcing material is added to the model information of the created whole tire model, stored in the memory 24 as an electronic file, and sent to the analysis unit 22.
[0021]
Next, finite element analysis 1 is performed (step 102).
In the finite element analysis 1, an internal pressure filling process and a load applying process are performed.
Specifically, the entire tire model 30 is moved to the road surface model side, which is a rigid plane prepared in advance, and the entire tire model 30 is reproduced in order to reproduce that the tire is assembled on the rim and the internal pressure is filled. While constraining a predetermined contour portion (a portion corresponding to the rim contact area) around the bead under a certain condition, the contour portions located on both sides are forcibly displaced so as to correspond to a predetermined rim width. A process of applying pressure to the inner peripheral surface of the rear tire overall model 30 is performed.
Further, thereafter, the entire tire model 30 is brought into contact with the road surface model, and a load load process for generating a predetermined load or a predetermined bending is performed.
[0022]
FIG. 4A shows a state immediately after the internal pressure filling process is performed in the entire tire model 30 shown in FIGS. 3A and 3B.
Due to the internal pressure filling process, the side portion is recessed inward (in the direction of the arrow) in the tire width direction.
FIG. 4B shows a state of the entire tire model 30 after the load processing. According to this, the entire tire model 30 is bent by the road surface model, and the side portion is convex outward (in the direction of the arrow) in the tire width direction.
Information on the analysis result calculated by the finite element analysis 1 is sent to the memory 24 and stored.
The information of the analysis result is the displacement of each node in the tire overall model 30 and the strain distribution and stress distribution of each finite element.
Steps 100 and 102 are steps for performing a finite element analysis of the entire tire, and correspond to the overall analysis step in the present invention.
[0023]
Next, a wire rod model and a base metal model are created in the model creating section 20 (step 104).
That is, for a reinforcing material having a wire and a rubber such as a carcass, a belt and a bead, a wire model and a base material model in which each of the wire and the rubber is discretized by a finite element are created.
[0024]
FIG. 5 shows a carcass model 34 obtained by modeling a part of the carcass model 32 in the whole tire model 30 shown in FIG.
The carcass model 34 includes a wire rod model 36 and a rubber rod model 38.
The wire rod model 36 is obtained by dividing a cylindrical shape having a circular cross section with a certain length into a plurality of solid elements by mesh-dividing along the circular shape. Are arranged in parallel. On the other hand, the rubber material model 38 is arranged so as to surround each of the wire models 36 arranged in parallel at regular intervals, divided into meshes and discretized into a plurality of solid elements. And In the example of FIG. 5, the carcass model 34 includes three wire rod models 36 and a rubber material model 38 surrounding the three wire rod models 36.
[0025]
The model information of the carcass model 34 including the wire model 36 and the rubber material model 38 is created, and the material parameters (Young's modulus, shear stiffness and Poisson's ratio) of the wire and the material parameter (Young's modulus) of the rubber are used. , Shear stiffness and Poisson's ratio), material information is added to the model information, stored in the memory 24 as an electronic file, and sent to the analysis unit 22.
[0026]
Next, the finite element analysis 2 is performed (step 106).
That is, the finite element analysis of the mechanical characteristics of the carcass is performed using the carcass model 34 using the information on the result of the finite element analysis 1 performed in step 102.
Specifically, the displacement of each node in the entire tire model in the internal pressure filling process or the internal pressure filling process and the load loading process obtained in the finite element analysis 1 and stored in the memory 24 is extracted, and the displacement of this node is used. Then, by displacing the boundary in the carcass model 34, the displacement of each node in the carcass model 34, the strain and the stress distribution of each finite element are calculated.
Information of the analysis result calculated by the finite element analysis 2 is sent to the memory 24 and stored.
[0027]
Next, a detailed wire rod model and a detailed base metal model are created in the model creating section 20 (step 108).
That is, a detailed model in which the configuration of the carcass is more detailed than the wire model 36 and the rubber material model 38 created in step 104 is created.
FIG. 6 shows a detailed model 40 obtained by modeling the configuration of one wire rod of the carcass model 34 shown in FIG. 5 in more detail.
In the detailed model 40, in the cross-sectional shape of the wire, three strands are twisted at the center, nine strands are twisted around the center, and 15 strands are twisted around the strand. This is a faithful reproduction of the configuration of a wire wound spirally with two strands and a configuration in which rubber is arranged around and between the strands.The overall shape is a cylindrical shape. are doing. That is, this is a model in which each strand is modeled, and the structure of the wire model composed of the strands is a twisted structure. In this case, the twist pitch, twist direction, and presence / absence of contact between the wires are modeled by the detailed model 40.
[0028]
The model information of the detailed model 40 including the detailed wire model and the detailed rubber material model is created, and the material parameters (Young's modulus, shear stiffness and Poisson's ratio) of each strand and the material parameter (Young's modulus) of the rubber material Ratio, shear stiffness, and Poisson's ratio), material information is added to the model information, stored in the memory 24 as an electronic file, and sent to the analysis unit 22.
[0029]
Next, the finite element analysis 3 is performed (step 110).
Here, the finite element analysis of the mechanical characteristics of the carcass is performed using the detailed model 40 using the information on the result of the finite element analysis 2 performed in step 110.
Specifically, the displacement of each node in the carcass model 34 obtained in the finite element analysis 2 and stored in the memory 24 is taken out, and the displacement of the node in the detailed model 40 is given by using the displacement of this node. , The displacement of each node in the detailed model 40, and the strain and stress distribution of each finite element.
Information on the analysis result calculated by the finite element analysis 3 is sent to the memory 24 and stored.
That is, as the finite element analysis 2 → 3 and the number of analyzes increases, the composite material is reproduced in more detail, and a wire model discretized by finite elements and a base material model surrounding this wire model are separately created. The finite element analysis of the mechanical characteristics of the carcass is performed using the information of the result of the finite element analysis performed one time earlier in the analysis. Steps 104 to 110 correspond to the partial analysis step in the present invention.
As described above, in the finite element analyzes 2 and 3 in the partial analysis step, the finite element analysis is performed based on the information on the result of the finite element analysis obtained in the finite element analysis 1 in the overall analysis step.
[0030]
Finally, the analysis result of the finite element analysis 3 is output to the display 16 or the printer 18 (Step 112).
FIGS. 7A and 7B show a detailed wire model 42 obtained by extracting only the wire portion in the detailed model 40, and display a region A obtained by the finite element analysis 3 (FIGS. 3A and 3B). 4B) and FIGS. 4A and 4B), the maximum principal stress distribution at the time of the internal pressure filling process is indicated by the level of the concentration. FIG. 7B shows the detailed wire rod model 42 shown in FIG.
M ₁ Indicates the direction of the bending moment acting on the detailed wire rod model 42 due to the internal pressure due to the internal pressure filling.
According to the distribution of the maximum principal stress, it is found that the internal wire filling process includes compression (high density area in the figure) and tension (low density area in the figure) in the wire direction in the detailed wire model 42. Bending moment M ₁ It can be seen that compression and tension are generated corresponding to the directions of. In addition, each strand changes its circumferential position of the detailed wire model 42 in a spiral shape due to the twisted structure, and it can be seen that the maximum principal stress distribution changes depending on this circumferential position.
[0031]
On the other hand, FIGS. 8A and 8B show the detailed wire rod model 42 and the region A (FIGS. 3A and 3B and FIGS. 4A and 4B) obtained by the finite element analysis 3. 4B shows the maximum principal stress distribution when the load is further applied after the internal pressure filling process in b)). FIG. 8B shows the partial model 42 shown in FIG.
M ₂ Indicates the direction of the bending moment acting on the detailed wire rod model 42 due to the load.
According to this, the main stress distribution different from that during the internal pressure filling process is shown by the load application process, and the bending moment M ₂ It can be seen that compression and tension are generated corresponding to the directions of. In addition, each strand changes its circumferential position of the detailed wire model 42 in a spiral shape due to the twisted structure, and it can be seen that the maximum principal stress distribution changes depending on this circumferential position.
[0032]
These analysis results are consistent with the results qualitatively expected from the direction of the bending moment acting by the internal pressure filling process and the load application process.
Therefore, the displacement of the node of the carcass model 32 at a desired position in the entire tire model 30 in the internal pressure filling process obtained in the finite element analysis 1 or the internal pressure filling process and the load applying process is extracted, and the displacement of the node is used. By displacing the boundaries between the carcass model 34 and the detailed model 40, the distribution of the stress and strain of the carcass at a desired position can be analyzed in detail and quantitatively up to the distribution in each strand.
[0033]
Therefore, each position of the carcass model 32 in the whole tire model 30 is analyzed using the detailed model 40, and for example, by examining the maximum principal stress distribution, the position having the lowest safety factor in terms of the physical properties such as the breaking strength of the strand is obtained. It is possible to develop a tire with excellent durability that does not break the strands while changing the twisted structure of the steel cord or the design specification of the tire so that the safety factor secures a predetermined level. Further, it is possible to know the possibility of the occurrence of cracks in the rubber material surrounding the strand of the steel cord from the strain distribution acting on the detailed base material model surrounding the detailed wire model 42.
Further, the level of the strain acting on the rubber material between the steel cords can be known from the strain distribution of the rubber material model 38 between the adjacent wire rod models 36 in the detailed model 40, and the crack of the rubber material located between the steel cords can be determined. It is also possible to know the possibility of occurrence.
In addition, since the finite element analysis is performed stepwise and finely like the whole tire model 30, the carcass model 34, and the detailed model 40, a model of the whole tire reflecting the configuration of the wire rod is accurately created to perform the fine finite element analysis. , It is possible to simulate the mechanical characteristics of the reinforcing member including the wire in a short time and with high accuracy.
[0034]
In the above embodiment, the internal pressure filling process and the load application process are performed in the finite element analysis 1 (step 102). However, the process of the overall analysis step corresponding to the finite element analysis 1 in the present invention is performed by the internal pressure filling process. The processing is not limited to the processing and the load processing, and processing used for various performance analysis may be performed. For example, in addition to the internal pressure filling process and the load loading process, a process of rolling the entire tire model 30 in a straight running state to reproduce a straight running state, a process of rolling by applying a slip angle to reproduce a cornering running, A process of providing a film and rolling on the film to reproduce the process leading to hydroplaning, and a process of reproducing vibration and noise by running on protrusions and uneven road surfaces to vibrate may be performed. Through the processing in these various performance analyses, the mechanical characteristics of reinforcing materials such as a carcass, a belt, and a bead when simulating various performance tests of a tire can be simulated with high accuracy in a short time.
Further, in the overall analysis step, a molding analysis process for analyzing the deformation process of the expanded green tire model immediately before vulcanization from the green tire model at the time of tire molding in the tire manufacturing stage may be performed. By the expansion processing of the raw tire model at the time of molding, the mechanical characteristics of the reinforcing material such as a carcass, a belt and a bead when the green tire is expanded can be simulated in a short time with high accuracy.
[0035]
When analyzing the mechanical characteristics of the carcass end in the carcass model 34 and the detailed model 40, the rigidity changes discontinuously at the end of the highly rigid wire, and the stress distribution and the strain distribution rapidly change. In order to accurately simulate the mechanical characteristics, it is preferable to model a region of the carcass including the carcass that is five times or more the thickness of the carcass as the carcass model in order to accurately simulate the dynamic characteristics. More specifically, from the viewpoint that a sufficient analysis result can be obtained efficiently, it is preferable to model a region of 10 times or less the thickness of the carcass. For example, in the case of the carcass model 34 shown in FIG. 5, a model having a thickness of 5 to 10 times in the thickness direction is created.
[0036]
In the above description, the carcass, which is a reinforcing material, was described as an example of a composite material.In addition to this, in addition to a composite material reinforced with a wire such as a belt or a bead, a plurality of wires were combined in a textile form. It may be a composite material. Further, the wire is not limited to the steel, but may be made of an organic fiber material.
Furthermore, the simulation method of the present invention can be applied to a case where a wire and a base material surrounding the wire are used to simulate the mechanical characteristics of a composite material embedded in a structure such as a building. it can.
[0037]
As described above, the method for simulating the mechanical properties of the composite material of the present invention has been described in detail.However, the present invention is not limited to the above-described example, and various improvements and modifications may be made without departing from the spirit of the present invention. Of course it is good.
[0038]
【The invention's effect】
As described in detail above, in the present invention, the dynamics in the detailed structure of a composite material having a wire and a base material surrounding the wire, for example, the structure of a twisted cord or textile included in a carcass or belt of a tire, and the like. The characteristics can be simulated with high accuracy in a short time, and can be effectively used for, for example, development of a tire having excellent durability. Further, it is possible to simulate the mechanical characteristics of the reinforcing material when simulating various performance tests of the tire in a short time and with high accuracy.
[Brief description of the drawings]
1 (a) and 1 (b) are configuration diagrams showing a configuration of a tire reinforcing material mechanical characteristic simulation apparatus for performing a composite material mechanical characteristic simulation method of the present invention.
FIG. 2 is a flowchart showing a flow of a method for simulating mechanical characteristics of a tire reinforcing material, which is an example of a method for simulating mechanical characteristics of a composite material according to the present invention.
FIGS. 3A and 3B are diagrams illustrating a finite element model created by the method for simulating the mechanical characteristics of a tire reinforcing material shown in FIG. 2;
FIGS. 4A and 4B are diagrams illustrating an example of an analysis result obtained by the method for simulating mechanical characteristics of a tire reinforcing material illustrated in FIG. 2;
FIG. 5 is a diagram illustrating a finite element model created by the method for simulating mechanical characteristics of a tire reinforcing member shown in FIG. 2;
6 is a diagram illustrating a finite element model created by the method for simulating mechanical characteristics of a tire reinforcing material shown in FIG.
FIGS. 7A and 7B are diagrams showing another example of the analysis result obtained by the method for simulating the mechanical characteristics of the tire reinforcing material shown in FIG. 2;
FIGS. 8A and 8B are diagrams showing another example of the analysis result obtained by the method for simulating the mechanical characteristics of the tire reinforcing material shown in FIG. 2;
[Explanation of symbols]
10 Mechanical property simulation device
20 Model creation unit
22 Analysis unit
24 memory
30 whole tire model
32,34 carcass model
36 wire rod model
38 Rubber material model
40 Detailed model
42 Partial model

Claims (4)

A method for simulating mechanical properties of a composite material embedded in a structure, comprising a wire and a base material surrounding the wire,
While creating a composite material model in which the composite material is discretized by finite elements as a uniform member without distinguishing the wire and the base material, material parameters of the composite material having the wire and the base material Expressed by an equivalent parameter as a uniform member, an overall analysis step of performing a finite element analysis of the entire structure including the composite material,
A wire model and a base material model are created by discretizing each of the wire and the base material with a finite element, and based on information on a result of the finite element analysis obtained in the overall analysis step, mechanical properties of the composite material A method for simulating mechanical properties of a composite material, the method comprising: In the partial analysis step, a finite element analysis is performed a plurality of times, and as the number of finite element analysis increases, the configuration of the composite material is reproduced in more detail to surround the wire model and the wire model discretized by the finite element. In the first finite element analysis, a finite element analysis of the mechanical properties of the composite material is performed using information on the result of the finite element analysis obtained in the overall analysis step, and a second finite element analysis is performed. 2. The method according to claim 1, wherein in the subsequent finite element analysis, the finite element analysis of the mechanical properties of the composite material is performed using information on the result of the finite element analysis performed one time before the analysis. In the case where the wire model is a model including the end of the wire, in the thickness direction of the composite, a region that is five times or more the thickness of the composite including the composite is modeled as a model of the composite. The method for simulating mechanical properties of a composite material according to claim 1. The mechanical characteristic of the composite material according to any one of claims 1 to 3, wherein the structure is a pneumatic tire including at least one of a twisted cord and a textile cord as the wire, and a rubber member as the base material. Simulation method.

Images