摘要(英) |
CAE (Computer Aided Engineering) analysis is a common tool to replace physical test. It often employs the Finite Element (FE) method to analyze and simulate the product design. In finite element method of CAE analysis, mesh generation is an indispensable operation. But, one of the problems found in going from CAD to CAE is that CAD models often feature a large number of faces, and many of them are much smaller than the desired finite element size. Specially, the appearing and existing of small blend faces on a CAD model affects the quality of analysis. It not only increases the analysis time but also produces poor simulation results. Hence, small blend face simplification on CAD models for mesh generation is essential to improve the quality of finite elements to analysis. This study develops the algorithms to simplify small blend faces for producing better models for FE based on the understanding the B-rep (Boundary representation) model. It includes the following main operations: generate new geometric data to replace all small blend faces, add new elements into B-rep, delete all elements related to small blend faces and update all topological data of the B-rep. All small blend faces can be suppressed, after the above operations are accomplished, which yields the simplified CAD model without small blend faces. The simplified CAD model without small blend faces will be obtained. In addition, several examples are presented to demonstrate the feasibility of the proposed method for small blend simplification. |
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