Preliminary Investigation of the Solution of Sparse Matrices in CATHENA

Abstract

CATHENA presently uses the Harwell MA28 routines to solve the sparse matrices generated by the thermalhydraulics section of the code. The objective of this paper is to present a short overview of commonly used sparse matrix solution techniques, and examine the potential benefits of using other solvers in CATHENA. A number of direct and iterative solvers have been tested on a stand-alone basis. Their performance was compared by solving CATHENA-generated non-positive definite, non-symmetric matrices taken from a variety of different simulations. The results of this preliminary investigation tend to indicate that some solvers may have advantages over the MA28 routines which could significantly enhance the peformance of CATHENA.