A parallel algorithm for the simultaneous solution of direct and adjoint multigroup diffusion problems.

In this paper, an acceleration scheme for the inverse power method based on the stationary properties of the Rayleigh ratio will be presented. Its practical use will be demonstrated by simultaneously solving the direct and adjoint multigroup diffusion problems. A parallel algorithm is developed using a repartition of both problems over two processors with a minimal communication effort. Speed-ups are given for a variety of problems on different computer architectures. [ABSTRACT FROM AUTHOR]