Experimental Study of the Efficiency of Parallel Solution of Three-Dimensional Boundary-Value Problems on Quasi-Structured Grids with Irregular Subgrids

An experimental study of the speedup and efficiency of parallel solution of three-dimensional boundary value problems on paralepipedal quasi-st ructured grids with irregular subgrids is carried out. The quasi-structured grids are constructed by dividing the computational domain by a structured parallelepipedal macrogrid into subdomains that are interconnected without overlapping. The subdomains contain their own structured parallelepipedal subgrids of two types: 1) regular, lying entirely within the domain and 2) irregular, containing parts of the boundary. The matching of solutions in the subdomains is carried out on the basis of a modification of the domain decomposition method developed by the authors. In this modification the original boundary value problem is replaced by some subproblems in the subdomains and Poincare–Steklov problems on the interfaces. The subproblems are solved on the subgrids, and the Poincare-Steklov equation by a direct approximation.