Balancing domain decomposition method for large-scale analysis of an assembly structure having millions of multipoint constraints

Abstract

A method by which to incorporate multipoint constraints (MPCs) into the balancing domain decomposition (BDD) method proposed in a previous study (BDD-MPC method) is investigated, improved, and applied to realistic and complex problems. First, the effects of the penalty term to take into account the MPCs in the coarse-grid problem of the BDD method are investigated. Then, improved implementation techniques for the BDD-MPC method are proposed. The computation speed of the projection procedure in the conjugate projected gradient method is improved using the block diagonal structure of the constraint matrix. The parallel solution procedure for the coarse-grid problem considering the MPCs that are projected to the coarse space is also improved. The improved MPC-BDD method is implemented in ADVENTURE_Solid, which is a parallel finite element structural analysis code. The code is parallelized using an MPI-OpenMP hybrid parallel implementation framework. In the previous study, the BDD-MPC method was applied to only simple numerical examples. In the present study the performance of the improved method is demonstrated by solving super-high-rise building models having very complex geometry and several million MPCs.