A MULTIZONE ADAPTIVE PARALLEL SCHEME FOR SOLIDIFICATION IN A RECTANGULAR CAVITY

A parallel algorithm has been developed to solve multi-zone solidification problems on MIMD (Multiple Instruction Multiple Data) and SPMD (Single Program Multiple Data) computer architectures. The parallel scheme is based on overlapping domain decomposition approach in which the global domain is divided into subdomains that overlap with their neighbors. The algorithm employs parallel adaptive grid generation and curvilinear finite volume discretization and is used here to solve the classical problem of solidification in a rectangular cavity. Each processor solves the governing equations on a subdomain. Inter-processor communication is restricted to the data on common grid cells at subdomain boundaries and is carried out using the Parallel Virtual Machine (PVM) message passing libraries. The results obtained here compare favorably with the existing experimental and numerical data. It is observed that, the speed up factor for parallel runs is not only a function of the physics of the problem, but also the way the grids are distributed to model the various physical phenomena accurately, and the manner in which spatial decomposition is carried out to distribute computational load on the processors.