An Algorithm in Element Deletion Process Used inMoving Three Zones Unstructured Grid for Arbitrary Relative Motion of Two Objects

Accurate solution of store separation problems requires fast generation of high quality grids in a large domain. This paper presents a procedure for the efficient generation of moving unstructured grids applicable to large displacement or deformation problems. A feature of the current work is its ability to eliminate and regenerate local grid points. An edge-based and a cellbased connectivity matrix have been employed simultaneously to prevent long searches through the listof edges. Compressed and highly deformed cells in angles are deleted while elongated cells are regenerated to maintain the overall grid quality. Quality is controlled by comparing cell size area of the deformed cells with desired local cell size. A fast algorithm is presented for element deletion process. This procedure is based on indexing, restructuring and deleting in data structure. A highlight of this procedure is that only grid cells in vicinity of the moving boundary are treated and the grids far away from the moving boundary remainundisturbed. The results are shown that this algorithm is sufficient for large displacements especially for relative motion of two objects.

Keywords:

Moving unstructured grid , Element deletionalgorithm , Restructuring of data structure , Connectivitymatrix , Three zones unstructured grid