Construction of Quasi-Structured Locally Modified Grids for Solving Problems of High Current Electronics

An algorithm for constructing quasi-structured grids, which consist of the uniform rectangular subgrids and are built in two stages, is considered. At first, the computational domain is covered by a uniform rectangular macrogrid, and then an original uniform rectangular subgrid is set for each macroelement. It is essential that subgrids can be inconsistent. By adjusting a density of the subgrid nodes an adaptation of the quasi-structured grid to inhomogeneities within the domain is achieved. To adapt the grid to the exterior boundary we make local modifications consisting in a shift of the near boundary nodes to the boundary. Here we propose the algorithm of the local modification to construct a quasi-structured grid of high quality which does not break a subgrid structuring. The suggested quasi-structured grids profitably differ from structured grids in that they do not require extra nodes to support structuring and, also, storing a large amount of information as for unstructured ones. The solution of boundary value problems for quasi-structured grids is found by a decomposition of the computational domain into subdomains without overlapping. This method can be easily parallelized and, therefore, used to carry out calculations on multiprocessor supercomputers.

Keywords

quasi-structured grids, local modification, domain decomposition method, boundary value problems, high-current electronics.

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