JP3127265B2 - CAE system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CAE (Computer Aided Engineer) that automates various tasks in design using a computer.
In particular, the present invention relates to a method for expressing data of a finite element model generated from a shape model and a method for constructing a CAE database.

[0002]

2. Description of the Related Art A conventional CAE system is composed of a preprocessor, an analysis program, and a postprocessor, as described in "Mechanical System Integrated Pre / Post Processor HICAD / CADAS / W Command Manual" (Hitachi, Ltd.). It consisted of two independent programs. First, the user creates a shape model representing the shape to be analyzed using the preprocessor, converts the shape model into a finite element model, and analyzes the converted finite element model with analysis attributes such as materials and boundary conditions. Enter the data. Next, the data group is converted into an input data format for analysis for executing the analysis, and analyzed using an analysis program. Finally, using a post-processor, the result of the analysis is converted into a data format for the post-processor, and the analysis result is displayed and edited.

In such a conventional CAE system, the shape data, finite element data, and analysis attribute data handled by the preprocessor and the data on the analysis result handled by the postprocessor are stored in independent databases without being associated with each other. Was stored.

[0004] For this reason, it has not been possible to directly use data relating to the analysis result in a preprocessor or directly use shape data, finite element data, attribute data, and the like in a postprocessor. For example, since the post-processor cannot directly use the information on the shape input by the pre-processor, if the analysis result is partially displayed for the analysis target having a complicated shape, the element number group of the finite element model can be directly specified, It has been necessary to specify a three-dimensional or two-dimensional space region, select a finite element group within the space region, and display the analysis results for those finite element groups.

[0005]

In the above-mentioned conventional CAE system, the pre-process until the analysis is performed and the post-process for evaluating the analysis result are completely independent in terms of both operation and data. . Therefore, even if the object to be analyzed is input to the computer as a shape model in the pre-process, once the shape model is converted into a finite element model, the subsequent processing is performed with an operation conscious of the shape model, for example, There is a problem that a finite element model cannot be operated in units of shape elements. In particular, when it is desired to partially display an analysis result of a complicated analysis target object in a post process, a considerable amount of time and labor is required. That is, the analysis attributes and the like cannot be confirmed without returning to the prepros, so that the number of operations of the CAE system is large and the operation time is long.

It is an object of the present invention to display a finite element model, input an analysis attribute, and display an analysis result, regardless of the stage of pre-processing or post-processing, when an object to be analyzed is input to a computer as a shape model. The object of the present invention is to provide a CAE system with good operability that can directly use data of shape elements constituting a shape model at any time.

[0007]

When a shape model representing an analysis target is divided into finite elements, the number of the shape element constituting the shape model is automatically added to each finite element as attribute information. When attribute information is added in this manner, a finite element group obtained by dividing the shape element can be searched by specifying the shape element. Conversely, if a finite element is specified, the shape element before division can be searched in reverse. By using this search means, it becomes possible to display a finite element model and to input an analysis attribute by designating a shape element.

[0008] The attribute information indicating the relationship between the shape element and the finite element is stored in the database by the database management unit common to the pre-process and the post-process similarly to the shape model and the finite element model. By using this attribute information, it is possible to partially display the analysis result by designating the shape element even in the post process.

That is, in order to achieve the above object, the present invention provides means for inputting a shape model or the like to be analyzed, a preprocessing unit for dividing the input shape model to generate a finite element model, In a CAE system including an analysis calculation section for analyzing a model, a post-processing section for displaying and evaluating the results of analysis, and a database for storing data such as a shape model, a finite element model, and an analysis result used in each section. Means for generating relation information relating the shape element of the shape model and the finite element generated from the shape element, and storing the relation information in the database;
Assumes that a means for searching display based on the at least one relationship information of each data corresponding to the designated shape element or finite elements.

[0010] Alternatively, the present invention provides a means for generating unique relational information for associating a shape element of a shape model with a finite element generated from the shape element and storing the information in a database; Means for searching and displaying at least one type of each of the data corresponding to the element or the finite element based on the relation information may be provided.

According to the present invention, when at least a part of the three-dimensional shape element number, the two-dimensional shape element number, and the one-dimensional shape element number indicating the shape element overlaps, the dimension of the shape element is identified. forming the assembled in relation information between the shape identification number and the shape element number or, characterized in that it constitutes the table of the finite element in the set of finite elements tables that are divided corresponding to the dimensions of the shape element.

The display of the finite element model, the input of the attribute information for analysis, the display of the analysis result, and the like can be executed for each unit of the shape element or a combination of the shape elements.

[0013]

In the CAE system of the present invention, the user
Through the input / output device, input a shape model to be analyzed, create a finite element model, input analysis attributes, execute analysis,
Performs a series of operations such as displaying analysis results. In this,
When creating a finite element model from a shape model by interactive operation or automatic processing, for finite elements generated by dividing shape elements such as lines, surfaces, and solid bodies that constitute the shape model, Information on which shape element is divided and generated is automatically added to each finite element.

The shape data, finite element data, shape-element relationship data, attribute data for analysis, and analysis output data handled by the CAE system of the present invention are related by a name uniquely assigned to one analysis target, and are stored in a database. It is stored in the database via the management unit.

When an analysis result is displayed, if a shape element or a combination of shape elements is designated, reference to the shape-element relation data enables the partial analysis result of an analysis object having a complicated shape to be analyzed. The display can be made easily.

[0016]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the overall configuration of an embodiment of the CAE system according to the present invention. The CAE system according to the present embodiment includes an input / output device 101 operated by a user interactively.
And a pre-processing unit 102 for creating input data for analysis
, An analysis calculation unit 103 that executes an analysis calculation, a post-processing unit 104 that displays an analysis calculation result, a pre-processing unit 102, an analysis calculation unit 103, and a post-processing unit 10.
4, a database 106 for storing a data group handled by
A database management unit 105 controls input / output of data of the database 106.

The flow of processing in this CAE system will be described. First, the user activates the pre-processing unit 102 via the input / output device 101 and creates the shape of the analysis target as a shape model. The created shape model is stored in the database 106 via the database management unit 105. At this time, the database management unit 105 adds the name given to the analysis target by the user in advance to the shape model and stores it in the database 106.

Next, the user divides the shape model using the pre-processing unit 102 to create a finite element model. Since the shape model is configured as a complex of shape elements such as a line, a surface, and a solid body, if each of the shape elements is divided into elements, the entire shape model is converted into a finite element model. These element division processes are performed interactively or automatically. At this time, the number of the shape element before division, that is, the line number or the surface number, is automatically added as attribute information of each finite element. The finite element model and the attribute information of the finite element are stored in the database 106 as in the case of the shape model.

As the last process of the pre-process, the user designates a finite element or a shape element, and inputs analysis attribute information such as material characteristics and boundary conditions to the finite element model. These attribute information for analysis are also similar to the above case,
Stored in the database 106. This ends the preprocessing.

Next, the user activates the analysis calculation unit 103 via the input / output device 101 and executes the analysis calculation. When the user executes the analysis process continuously from the pre-process, the data group created in the pre-process is directly converted into the input format for analysis, and the analysis calculation is started. On the other hand, when the process is interrupted once and the analysis process is started again, all related data groups are extracted from the database 106 via the database management unit 105 using the name given to the analysis object in advance, and then converted to the analysis input format. Convert and start analysis calculation. The analysis result by the analysis calculation is stored in the database 106 as in the case of the shape model and the finite element model described above. This ends the analysis process.

Finally, the user activates the post-processing unit 104 via the input / output device 101 to display and edit the analysis result. At this time, by using the related information between the shape element and the finite element created in the pre-process and specifying the number of the shape element, the analysis result of only the shape element portion can be displayed.

Next, the relationship information between the shape element and the finite element and the generation process thereof in the present invention will be described. FIG. 2 is a diagram showing the relationship between a shape model and its shape elements. The shape model 201 includes two one-dimensional shape elements 202
, One two-dimensional shape element 203 and one three-dimensional shape element 204. There are various ways to divide the shape model into shape elements, and the user can freely divide the shape model so that the user can easily process it by a later operation. For example, if different portions of the material are formed as different shape elements, and portions having different thicknesses are formed as different two-dimensional shape elements, the efficiency of inputting the attribute information for analysis is increased.

FIGS. 3, 4, and 5 show one-dimensional,
It is a figure showing the example which divided a two-dimensional and a three-dimensional shape element into a finite element. The shape element 301 in FIG. 3 is divided into five finite elements 302. The number of the shape element 301 is added to every finite element 302 as an attribute. Similarly, in the case of FIG. 4, the shape element 401 includes 32 finite elements 402.
And all the finite elements 402 include a shape element 4
The number 01 is added as an attribute. Similarly, in the case of FIG. 5, the shape element 501 is divided into 40 finite elements 502, and the number of the shape element 501 is added as an attribute to all the finite elements 502.

FIG. 6 shows an example of a specific data structure of these shape elements, finite elements, and relation information. The three-dimensional shape element includes a solid number for identifying a solid, solid topological data indicating a relationship between a surface, an edge, and a vertex of the solid, and geometric characteristics of the solid, that is, characteristics of a position and a shape of the solid. This is represented by a solid entity table 601 including solid entity geometric data. The two-dimensional shape element is represented by a surface table 602 including a surface number, surface topology data, and surface geometric data. The one-dimensional shape element is represented by a line table 603 including a line number, line phase data, and line geometric data. On the other hand, the finite element is represented by a finite element table 604 including an element number, an element type, and a node number constituting the finite element.

The relationship information between the shape element and the finite element is generated by describing the number of the shape element in the finite element attribute table 605 corresponding to the finite element table 604. The solid body number, surface number, and line number are, for example, 001 to 099, 100 to 199, and 200 to 29, respectively.
If they do not overlap each other as in FIG. 9, the data structure shown in FIG. 6 is sufficient. Further, the solid body number, the surface number, and the line number are, for example, 001 to 099, 050 to 149, respectively.
050 to 099 or 100 as in 100 to 249
-149 overlap each other, as shown in FIG.
A shape identification number for identifying the dimension of the shape element is added in combination with the shape element number. Alternatively, as shown in FIG. 8, a finite element table is divided according to the dimension of the finite element, and a shape element number is added to each.

Finally, a method of displaying an analysis result on a partial shape using the above-described relationship information between the shape element and the finite element will be described. FIG. 9 is a diagram showing a display procedure when the user understands the shape element numbers of the partial shapes to be displayed. The user inputs a desired shape element number via the input / output device 101. The post-processing unit 104 refers to the shape element numbers added to the above-described finite elements, selects all the finite elements identical to the shape element numbers input by the user, and determines the selected finite element group and their physical quantities. indicate.

FIG. 10 is a diagram showing a display procedure when the user does not know the shape element number of the partial shape to be displayed. The finite element included in the partial shape to be displayed is designated from the finite element model displayed on the screen, and the shape element number is inversely searched from the finite element. After that, based on the inversely searched shape element number, the same processing as in FIG. 9 is performed.
By the above means and procedure, the user can easily and partially indicate the analysis target having a complicated shape and easily display the analysis result.

Here, only the example of displaying the analysis result based on the searched shape element number has been described. However, the shape data, the finite element data, the shape-element relation data, the attribute data for analysis, the analysis output data It should be clear that any of these or combinations thereof can also be displayed. Further, a method in which an analysis result is superimposed on a shape model and displayed may be adopted.

[0029]

According to the present invention, a finite element model is displayed in a preprocess, an attribute for analysis is input, an analysis result is displayed in a postprocess, etc., using the number of the shape element defined at the time of inputting the shape model. Can be easily executed.
Therefore, even when analyzing a complicated shape model or the like, the desired portion of the shape can be accurately and easily operated or displayed, and the operability of the system is improved.

In particular, by sharing the database between the pre-process and the post-process, it is possible to refer to each data of the pre-process even in the post-process, and to confirm the analysis attributes and the like without returning to the pre-processor. As a result, the number of operations and the operation time of the CAE system can be significantly reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an overall configuration of an embodiment of a CAE system according to the present invention.

FIG. 2 is a diagram showing a relationship between a shape model and its shape element.

FIG. 3 is a diagram showing an example in which a one-dimensional shape element is divided into finite elements.

FIG. 4 is a diagram illustrating an example in which a two-dimensional shape element is divided into finite elements.

FIG. 5 is a diagram showing an example in which a three-dimensional shape element is divided into finite elements.

FIG. 6 is a diagram showing an example of a specific data structure of a shape element, a finite element, and relation information.

FIG. 7 shows a case where the shape element table numbers partially overlap.
It is a figure which shows the example of the specific data structure of the shape element, the finite element, and the related information which added the shape identification number which identifies the dimension of a shape element to the shape element number, and was made into related information.

FIG. 8 shows a case where the shape element table numbers partially overlap.
It is a figure which shows the example of the concrete data structure of the shape element, the finite element, and the related information which divided the finite element table according to the dimension of the finite element, added the shape element number to each, and made it related information. .

FIG. 9 is a diagram showing a display procedure of an analysis result when a user inputs a shape element number.

FIG. 10 is a diagram showing a display procedure of an analysis result when a user designates a finite element instead of inputting a shape element number.

[Explanation of symbols]

Reference Signs List 101 input / output device 102 preprocessing unit 103 analysis calculation unit 104 post processing unit 105 database management unit 106 database 201 shape model 202, 203, 204, 301, 401, 501 shape element 302, 402, 502 finite element 601, 602, 603 , 701,702,703,8
01, 802, 803 Shape element data structure 604, 704, 804, 806, 808 Finite element data structure 605, 705, 805, 807, 809 Data structure of relationship information indicating relationship between shape element and finite element

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-231374 (JP, A) IPSJ 40th (Early 1990) National Conference Proceedings 1530-1531 pages Eiji Miyanaka et al. Intermediate file generation device that integrates data, conditions, and mesh data ”(58) Field surveyed (Int.Cl. ⁷ , DB name) G06F 17/50 612 JICST file (JOIS)

Claims (4)

(57) [Claims] A means for inputting a shape model or the like to be analyzed; a preprocessing unit for dividing the input shape model to generate a finite element model; an analysis calculation unit for analyzing the finite element model; In a CAE system comprising a post-processing unit for displaying and evaluating data, and a database for storing data such as a shape model, a finite element model, and an analysis result used in each of the units, a CAE system comprising: Means for generating relational information relating the generated finite element and storing the relational information in the database; and searching and displaying at least one type of each of the data corresponding to a designated shape element or finite element based on the relational information. And a three-dimensional shape element number indicating the shape element and a two-dimensional shape
At least part of the prime number and the one-dimensional shape element number overlap
The relationship information identifies the dimension of the shape element.
A CAE system comprising a set of another shape identification number and said shape element number . 2. A means for inputting a shape model or the like to be analyzed, a preprocessing unit for dividing the input shape model to generate a finite element model, an analysis calculation unit for analyzing the finite element model, and a result of the analysis In a CAE system comprising a post-processing unit for displaying and evaluating data, and a database for storing data such as a shape model, a finite element model, and an analysis result used in each of the units, a CAE system comprising: Means for generating relational information relating the generated finite element and storing the relational information in the database; and searching and displaying at least one type of each of the data corresponding to a designated shape element or finite element based on the relational information. And a three-dimensional shape element number indicating the shape element and a two-dimensional shape
At least part of the prime number and the one-dimensional shape element number overlap
The table of the finite element has the shape
A set of finite element tables divided according to the element dimensions
CAE system characterized in that it consists of. 3. A means for inputting a shape model or the like to be analyzed, a preprocessing unit for dividing the input shape model to generate a finite element model, an analysis calculation unit for analyzing the finite element model, and a result of the analysis In a CAE system comprising a post-processing unit for displaying and evaluating data, and a database for storing data such as a shape model, a finite element model, and an analysis result used in each of the units, a CAE system comprising: Means for generating unique relation information relating to the generated finite element and storing it in the database; and searching for at least one type of each of the data corresponding to a designated shape element or finite element based on the relation information And a means for displaying and displaying a three-dimensional shape element number indicating the shape element and a two-dimensional shape information.
At least part of the prime number and the one-dimensional shape element number overlap
The relationship information identifies the dimension of the shape element.
A CAE system comprising a set of another shape identification number and said shape element number . 4. A means for inputting a shape model or the like to be analyzed, a preprocessing unit for dividing the input shape model to generate a finite element model, an analysis calculation unit for analyzing the finite element model, and a result of the analysis A CAE system including a post-processing unit for displaying and evaluating the data, and a database for storing data such as a shape model, a finite element model, and an analysis result used in each of the units. Means for generating unique relational information relating the generated finite element and storing it in the database; and searching for at least one type of each of the data corresponding to a designated shape element or finite element based on the relational information And a means for displaying and displaying a three-dimensional shape element number indicating the shape element and a two-dimensional shape information.
At least a part of the prime number and the one-dimensional shape element number overlap
The table of the finite element has the shape
A set of finite element tables divided according to the element dimensions
CAE system characterized in that it consists of.