JP2005266886A - Creation method and creation device of impregnation analysis model - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a creation method of an impregnation analysis model which can automatically define an impregnation coefficient for each element, attain an improvement in analysis accuracy and the automation of model creation, provide a creation device and a computer program or a storage medium. <P>SOLUTION: A creation method of an impregnation analysis model which calculates an impregnation process of resin to a metal mold using a computer 100 has: an element configuration data creation means 106 to form element configuration data 119 from CAD data 115; an element thickness data computing means 107 to calculate element thickness data 120 from the CAD data and the element configuration data; and a material physical property data computing means 108 to calculate material physical property data 121 of each element from the element thickness data, creating condition data 118, and a material physical property database 117. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an impregnation process of a resin impregnated into a porous medium such as a carbon fiber woven material in an impregnation molding method such as an RTM molding method (Resin Transfer Molding molding method) used for molding a composite material. The present invention relates to a method and apparatus for creating an impregnation analysis model in a resin impregnation analysis obtained using a numerical analysis method such as a method, a computer program thereof, and a storage medium.

  In the RTM molding method, a porous medium (hereinafter referred to as a base material) such as a woven material (cross material) or a mat material made of carbon fiber or glass fiber is referred to as a cavity (hereinafter referred to as a cavity). This is a molding technique in which an FRP molded product is obtained by injecting resin into the cavity.

Conventionally, as a technique for performing CAE (Computer Aided Engineering) analysis using a computer for the resin impregnation process in the RTM molding method, a method as shown in Document 1 is known.
In injection molding and impregnation molding typified by the RTM molding method, flow conductance is used as an index indicating the ease of resin flow in the cavity, but the definition formula is shown below for injection molding and impregnation molding. So different.

Flow conductance of injection molding = − (wall thickness × wall thickness) / (12 × resin viscosity) (1)
Flow conductance of impregnation molding =-(impregnation coefficient) / (resin viscosity) (2)
According to the equation (1), the flow conductance in the injection molding analysis is calculated based on the thickness distribution of the cavity and the resin viscosity of the injected resin, whereas the flow conductance in the impregnation molding according to the equation (2) It is calculated on the basis of the impregnation coefficient and resin viscosity, which are indicators of ease. That is, since the flow conductance calculation in the injection molding analysis can be calculated from the shape and the physical properties of the resin used, the wall thickness is automatically calculated from CAD (Computer Aided Design) data of the molded product as in Reference 2. If technology is used, automation is possible.

However, in the case of impregnation molding, it has been a problem that an impregnation coefficient depending on the wall thickness, base material type, base material lamination angle, temperature, pressure and the like is required. That is, since the type, thickness, temperature, and pressure of the base material vary depending on the model location, there is a problem that it cannot be determined at the model creation stage.
That is, the flow conductance cannot be automatically calculated in advance from the element shape to be molded. According to the conventional technique, the person in charge calculates the flow conductance after estimating an appropriate impregnation coefficient in the impregnation analysis. However, there is only a method, and it takes not only a half day or more to create a CAE analysis model, but also there is a problem in the accuracy of the analysis result.
JP 2003-11170 A JP-A-10-124555

  The present invention solves the above-mentioned problems of the prior art and is an impregnation analysis model that can automatically define an impregnation coefficient that is an index indicating the ease of resin flow in a cavity in an RTM molding method or the like with respect to a CAE analysis model. An object is to propose a creation method, a creation device, a computer program, and a storage medium.

  In order to achieve the above object, a method for creating an impregnation analysis model according to the present invention is a method for creating an impregnation analysis model in which the impregnation process of a resin into a base material arranged in a mold is calculated using a computer. Generating element shape data from CAD data, calculating element thickness data to calculate element thickness data from the CAD data and the element shape data, and the element thickness data. A material physical property data calculation process for calculating the material physical property data of each element from the molding condition data and the material physical property database is performed.

  The impregnation analysis model creation apparatus of the present invention is an impregnation analysis model creation apparatus for calculating the impregnation process of a resin in a base material arranged in a mold by using a computer, and the element shape is obtained from CAD data. Element shape data creating means for generating element thickness data calculating means for calculating element thickness data from the CAD data and the element shape data, element thickness data, molding condition data, and material property database And material physical property data calculating means for calculating material physical property data of each element.

  Furthermore, the present invention includes a computer program for executing each step using a computer in the method for creating an impregnation analysis model, and a computer-readable storage medium storing the computer program. In the present invention, the CAD data indicates shape data of a molded product input by a CAD system operating on a computer. The CAE analysis is a calculation method using a computer. The CAE analysis model used in the CAE analysis of the impregnation molding is an element shape data such as nodes and elements used in the impregnation analysis and a material such as an impregnation coefficient. It refers to model data that includes at least physical property data and is calculated by a computer.

  According to the present invention, an element shape data creating step for generating element shape data from CAD data, an element thickness data calculating step for calculating element thickness data from the CAD data and the element shape data, By having the material physical property data calculation process for calculating the material physical property data of each element from the element thickness data, the molding condition data, and the material physical property database, the creation of the CAE analysis model in the impregnation analysis can be automated. Analysis model creation time can be greatly reduced. In addition, since the accuracy of the analysis model is increased, the impregnation process can be simulated with high accuracy, which can greatly contribute to high quality, high efficiency, and low cost in product development.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, exemplary embodiments of the invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of an apparatus for creating an impregnation analysis model of the present invention. In this embodiment, 100 is a computer (control device), 101 is a keyboard, 102 is a mouse, 103 is a display, and 104 is a storage device. As the storage device 104, a removable auxiliary storage device such as ZIP, MO, PD, CD-R, DVD, magnetic tape, etc. can be used in addition to the hard disk device.
The storage device 104 includes CAD data storage means 111, CAE analysis model storage means 112, material property database storage means 113, molding condition data storage means 114, and element thickness data storage means 122. CAD data 115 is stored in the CAD data storage unit 111, a CAE analysis model 116 is stored in the CAE analysis model storage unit 112, a material physical property database 117 is stored in the material physical property database storage unit 113, and a molding condition data storage unit 114 is stored in the molding condition data storage unit 114. The molding condition data 118 is stored, and the element thickness data storage means 122 stores the element thickness data 120. These storage means do not need to be included in one storage device 104, and may exist in a plurality of computers connected by a network, or may exist in a plurality.

  The computer 100 includes CAD data input means 105, element shape data creation means 106, element thickness data calculation means 107, and material property data calculation means 108.

  FIG. 2 is a diagram illustrating a data structure of the CAE analysis model 116. The CAE analysis model 116 includes at least element shape data 119 created by the element shape data creation means 106 and material property data 121 calculated by the material property data calculation means 108. The data stored in the material property database 117 includes at least impregnation coefficient data. As an example, a method for measuring impregnation coefficient data will be described below.

  In the resin impregnation process in the RTM molding method, it is known that the behavior of the resin impregnated in the substrate follows the DARCY rule shown in the following equation, and the flow rate Q (m3) impregnated per unit time is represented by the following equation: can get.

Q = (K × A / μ) × (ΔP / ΔL)
Here, K (m2) is an impregnation coefficient, A is a cross-sectional area (m2), μ is a resin viscosity (Pa · s), and ΔP (Pa) / ΔL (m) is a pressure gradient per unit length. If this equation is integrated with the arrival time t (s), the impregnation coefficient K is obtained by the following equation.

K = (L × L × μ) / (2 × P × t)
From this equation, the impregnation coefficient K can be calculated if the distance L (m) from the resin inlet to the flow front (the tip of the fluid resin) and the arrival time t (s) are known. Therefore, the impregnation coefficient is measured by molding a basic shape molded product such as a flat plate as an example, and measuring the resin viscosity μ, flow front L, and arrival time t therefor, the impregnation coefficient K is calculated. it can.

Parameters to be considered in the impregnation coefficient include flow front L (m), arrival time t (s), plate thickness h (m), substrate type X, substrate lamination number N, substrate lamination angle θ ( The molding temperature T1 (degree), the mold temperature T2 (degree), the molding pressure P (Pa), etc. may be added. It is not necessary to consider all these parameters, but it is necessary for the designer to consider the design factors that are considered to have an influence on the impregnation coefficient in consideration of the model shape.
Further, the data such as the impregnation coefficient included in the material property database 117 may be obtained by, for example, a molding experiment using a simple shape, or may be obtained by a calculation simulation of a molding process.

  Next, FIG. 3 is a flowchart showing a work flow related to the CAE analysis model creation method of the present embodiment.

First, element shape data 119 is created from CAD data 115 contained in the storage device 104 of FIG. 1 (S101), then element thickness data 120 for each element is calculated (S102), and finally each element The material property data 121 is calculated (S103) and output to the CAE analysis model storage means 112 as the CAE analysis model 116 (S104).
A detailed description of each of the above steps will be given below.
FIG. 4 is a flowchart showing the operation in the element shape data creation step (S101).

  First, the CAD data input means 105 in FIG. 1 reads the CAD data 115 stored in the CAD data storage means 111 into the computer 100 (S201), and generates a neutral plane (S202). Then, a shell element is generated on the generated neutral plane (S203), and is output to the CAE analysis model 116 as element shape data 119 (S204). FIG. 7 shows an example of CAD data 115 and element shape data 119 output using the CAD data 115. 7A shows the input CAD data, and FIG. 7B shows the element shape data generated on the neutral plane. The method for automatically generating a CAE analysis model from CAD data in this way is an existing technology already installed in many CAD software such as IDEAS, CATIA, and UNIGRAPHICS (hereinafter, registered trademark).

  FIG. 5 is a flowchart showing the operation in the element thickness data creation step (S102).

  First, the CAD data 115 is read (S301), and the element shape data 119 created in S101 is read (S302). Then, using the thickness calculation method described in Document 2 or the like, the thickness of each element included in the element shape data is calculated with reference to the CAD data 115 from the position information of each node included in the element shape data 119. (S304). This is repeated for the number of elements (S303), and is output to the element thickness data storage means 122 as element thickness data 120 (S305). Such a wall thickness calculation method is also an existing technology installed in the CAD software and pre-post software used for CAE analysis.

FIG. 6 is a flowchart showing the operation in the material property data creation step (S103) of each element, which is a novel technique of the present invention.
First, the molding condition data 118 included in the molding condition data storage unit 114 is read (S401), and then the element shape data 119 calculated in S101 is read from the CAE analysis model 116 (S402). Then, the element thickness data 120 calculated in S102 is read (S403), and further the material physical property database 117 stored in the material physical property database storage means 113 is read (S404).

  Next, the material physical property data for each element is calculated by referring to the material physical property database 117 based on the thickness, base material type, number of base material layers, base material layer structure, pressure, temperature, and the like (S406). This operation is performed for each element (S405), and the material physical property data 121 is output into the CAE analysis model 116 (S407). By this series of operations, material property data corresponding to the thickness, base material type, and base material stack number of each element can be automatically calculated, and a highly accurate CAE analysis model can be created.

  In each step shown in FIGS. 4 to 6, the format of reading all data from the database at one time has been described. However, only necessary data may be sequentially referred to the database. In addition, in order to shorten the time, the read contents of the previous process may be taken over and used.

  The above embodiment is implemented by a computer 100, a storage unit 104, and a program including CAD that operates them. Such programs and data in various storage means are stored in a computer-readable tangible medium such as a floppy (registered trademark) disk, ZIP, MO, PD, CD-R, DVD, magnetic tape, or a wired or wireless network. It is distributed using transmission means.

Embodiments of the present invention will be described below with reference to the drawings.
(Example 1)
In this example, as shown in FIG. 8, impregnation analysis was performed on a flat plate shape having an outer dimension of 300 × 1400 mm and a thickness of 2 to 5 mm, and is data stored in CAD data 115. . Carbon fiber "TORAYCA" plain weave cloth CO6343 made by Toray Industries Co., Ltd. was laminated as 4 ply (lamination angle: 0 degree / 45 degrees / 45 degrees / 45 degrees) as the base material used, and the main resin made by JER Co., Ltd. " A matrix resin of Epicoat “1750” and “Epicure” W manufactured by JER Co., Ltd. was used. The stacking angle was 1 degree in the longitudinal direction of 1400 mm. The resin temperature was 40 degrees, the mold temperature was 60 degrees, the impregnation pressure was 1 atm, the impregnation coefficient for each thickness was obtained in advance by experiments, and a physical property database was defined.

  First, in step S101 of FIG. 3, CAD data 115 is input by CAD data input means 105 included in computer 100 of FIG. 1, and element shape data 119 is formed on the neutral plane of the flat plate by element shape data creation means 106. A shell element was created (FIG. 9). The element used was a two-dimensional shell element, and an element having a length of about 30 mm was automatically created (number of nodes 528, number of elements 470).

Next, in step S102, the thickness of each element was calculated, and a value of 2 to 5 mm was obtained. The thickness of the plate differs from place to place, and in this model, there were 47 kinds of thickness.
Finally, in step S103, the impregnation coefficient is calculated for each element with reference to the material property database 117 based on the element shape data 119, the element thickness data 120, and the molding condition data 118 for each element, and CAE An analysis model was output.

The creation time of the analysis model based on the above flow was about 5 minutes, which was greatly reduced compared to the conventional method.
In order to verify the validity of the modeling method, an impregnation analysis using the output CAE analysis model and an actual test using the same test piece were performed, and the results were compared. The impregnation analysis program was developed in-house.

  The relationship between the flow front L and the impregnation time t was compared in the case where the resin was impregnated from the line 1 shown in FIG.

  FIG. 10 shows the filling time t (s) on the horizontal axis and the flow front L (mm) on the vertical axis. The analysis result is indicated by a solid line, and the experimental result is indicated by ●. As shown in this figure, the experimental results and the analysis results almost coincided, and the impregnation process could be simulated with high accuracy by defining the physical properties in detail.

  The present invention is not limited to a method for creating an impregnation analysis model, and can be applied to a method for creating an analysis model of an object in which a shape factor is taken into a physical property value. For example, the present invention can be applied to a method for creating an acoustic analysis model that requires impedance, a method for creating a permeation analysis model for a porous body, and the like, but the application range is not limited thereto.

It is a block diagram which shows the structure of one Embodiment of the computer used for the preparation method of the impregnation analysis model of this invention. It is explanatory drawing of the element which comprises the CAE analysis model contained in the memory | storage device of the computer of FIG. It is a flowchart which shows the preparation method of the impregnation analysis model of this invention. It is a flowchart which shows the operation | movement of creation of the element shape data in FIG. It is a flowchart which shows the operation | movement of the calculation of the element thickness data in FIG. It is a flowchart which shows the operation | movement of the calculation of the material physical property data in FIG. It is CAD data shape and element shape data in the example of an embodiment of the present invention. It is a three-dimensional view of the CAD data shape in the Example of this invention. It is a three-dimensional view of element shape data in the example of the present invention. It is a comparison graph of the impregnation analysis result and the impregnation experiment result in the Example of this invention.

Explanation of symbols

100: Computer
101: Keyboard
102: mouse
103: Display
104: Storage device
105: CAD data input means
106: Element shape data creation means
107: Element thickness data calculation means
108: Material property data calculation means
111: CAD data storage means
112: CAE analysis model storage means
113: Material physical property database storage means
114: Molding condition data storage means
115: CAD data
116: CAE analysis model
117: Material property database
118: Molding condition data
119: Element shape data
121: Material property data
122: Element thickness data storage means
120: Element thickness data

Claims (12)

  A method of creating an impregnation analysis model for calculating a resin impregnation process in a base material arranged in a mold using a computer, the element shape data creating step for generating element shape data from CAD data, Material thickness data calculation step for calculating element thickness data from CAD data and element shape data, and material for calculating material property data of each element from the element thickness data, molding condition data, and material property database A method for creating an impregnation analysis model characterized by undergoing a physical property data calculation step.   2. The method for creating an impregnation analysis model according to claim 1, wherein the calculation step of the material property data is a step of calculating the material property data from the material property database.   The material physical property database includes a numerical value or data representing a relationship between at least one information of thickness, base material type, base material stacking number, base material stacking angle, pressure, temperature and the material physical property data, a table The method for creating an impregnation analysis model according to claim 1, wherein at least one piece of information among the functions is stored.   The method for creating an impregnation analysis model according to any one of claims 1 to 3, wherein the material property data includes an impregnation coefficient indicating the ease of resin flow.   The impregnation analysis model creation method according to claim 1, wherein the element shape data creation step is a step of automatically creating from the CAD data.   A device for creating an impregnation analysis model for calculating a resin impregnation process in a base material arranged in a mold using a computer, element shape data creating means for generating an element shape from CAD data, and the CAD data Element thickness data calculation means for calculating element thickness data from the element shape data, and material property data calculation for calculating material property data of each element from the element thickness data, molding condition data, and material property database And an impregnation analysis model creating apparatus.   7. The impregnation analysis model creation apparatus according to claim 6, wherein the material property data creation means is means for calculating the material property data from the material property database.   The material physical property database includes a numerical value or data representing a relationship between at least one information of thickness, base material type, base material stacking number, base material stacking angle, pressure, temperature and the material physical property data, a table The apparatus for creating an impregnation analysis model according to claim 6 or 7, wherein information on at least one of the functions is stored.   The impregnation analysis model creation apparatus according to any one of claims 6 to 8, wherein the material property data is an impregnation coefficient indicating ease of resin flow.   7. The impregnation analysis model creation apparatus according to claim 6, wherein the element shape data creation means is means for automatically creating from the CAD data.   The computer program for performing each process in the preparation method of the impregnation analysis model of Claim 1 using a computer.   A computer-readable storage medium storing the computer program according to claim 11.

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