摘要(英) |
Mold flow analysis allows designers of plastic parts to confirm possible problems during the actual manufacturing of the product during the design stage. Before performing mold flow analysis, the CAD model of the product must be converted into solid grid data and provided to the analysis software for calculation. The quantity and quality of the solid grid will respectively affect the calculation time and analysis accuracy of the simulation analysis. If you need faster analysis time and accurate analysis results, you need to build a hexahedral grid, but the current hexahedral grid needs to cut the model manually, and then build the hexahedral grid. In order to improve the efficiency and accuracy of hexahedral grid construction, the laboratory has developed CAD model volume decomposition technology, which decomposes the model into several blocks with relatively simple shapes, and constructs grid data from the blocks in a programmatically automated manner . This research is to optimize and improve the insufficient part of the previously developed volume decomposition algorithm to improve the integrity of the model decomposition, and finally combine the automatic quadrilateral mesh construction technology to achieve the efficiency of quickly converting the CAD model into a mesh. First, the decomposition algorithm is modified in order to decompose the shell body connected to the external raised features and to correct the wrong block outline caused by the blind hole feature. Finally, in order to ensure that grid interlacing does not occur after grid construction, the correspondence between different blocks must be established to provide complete block data for automatic grid construction. This study will be compared with literature [13]. Under the same 24 cases, the number of constructed blocks will increase by 180, and the success rate will increase from 95.0% to 99.3%, effectively reducing the number of block construction failures. |
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