Parallel adaptive multigrid with nonlinear krylov subspace acceleration for steady 3D CFD problems

摘要

This paper deals with 3D parallel adaptive multigrid methods for solving CFD problems on block-structured curvilinear grids. The multigrid strategy adopted is the Multilevel Adaptive Technique (MLAT), introduced in [1]. A high-level communications library takes care of all the communication necessary for solving these problems on MIMD machines. In case of locally refined grids this means that next to the communication on interior boundaries of grid partitioned blocks also volumes of data have to be shifted from one processor to another in order to achieve a satisfactory load balancing. A new smoother for higher order upwind discretizations and a nonlinear Krylov subspace acceleration of multigrid are included.