Parallel computation of multiphase flow in saturated porous media

Abstract

In order to handle large domain problems of multiphase flow simulation and also to reduce the computational time, a parallel computational model is developed for the fully implicit two dimensional two phase flows using both simultaneous and modified sequential approach. In the simultaneous approach, both the governing equations are solved simultaneously whereas in the sequential approach the governing equations are solved sequentially. The parallel computations are carried out in such a way that the domain is discretized into number of subdomains and the computation of each sub domain is carried out in one processor. The parallel computational models are compared using the results of conventional computation. In this study the domain decomposition is carried out using both row wise and column wise overlapping domains. It is observed that the parallel computational model is able to reduce the computational time and increase the computational speedup especially in the case of larger domain problems. The parallel computation is carried out on IBM SP-2 scalable parallel machine with 32 processor using Message Passing Interface (MPI) programming and the number of processor required for the simulation depends on the size of the domain. It is also observed that modified sequential approach of parallel model requires more elapsed time than the simultaneous approach of parallel model. The decompositions such as column wise and row wise decompositions are equally good with reference to the elapsed time of simulation.