Parallel Three-Dimensional LAD Model on Cartesian Grids of nested structure
This preprint addresses generalization of the technology of nested-type Locally Adaptive (LAD) Cartesian grids to the three-dimensional case, and description of the corresponding software library. The library is written in C++ programming language using object-oriented programming principles and adapted for parallel computing on multi-core shared memory processes using OpenMP application interface. The library takes into account the specificity of multi-threaded 3D problems calculations with Cartesian grids. This can significantly minimize the used computer memory by not storing grid information. Data grid as the coordinates of the nodes, normals, areas, and volumes are not stored, and are evaluated as needed. The loop order over cells is represented by a special list, which simplifies parallel implementation by means of OpenMP directives. The preprint includes description of tree-like data structure on the LAD, basic principles of the discrete model, and main functions of the library developed. Preliminary results of testing the library and the estimation of the effectiveness of parallel calculations are given for calculations of the problem on explosion evolution in a closed domain.