ON THE EQUIVALENCE OF DISCONTINUOUS FINITE-ELEMENT METHODS AND DISCRETE ORDINATES METHODS FOR THE ANGULAR DISCRETIZATION OF THE LINEARIZED BOLTZMANN-EQUATION IN SLAB GEOMETRY

We describe the equivalence of discontinuous finite element methods an d discrete ordinates methods for the angular discretization of the Bol tzmann equation in slab geometry. We use the spectral Green's function (SGF) numerical method to solve the discrete ordinates equations on a digital computer. The SGF method is completely free from spatial trun cation errors; therefore, we use the 'exact' solution generated by the SGF method to reconstruct the flux profile inside each node of the sp atial grid. This scheme is referred to as the domain decomposition rec onstruction scheme. Numerical results to three typical problems are pr esented. (C) 1997 Elsevier Science Ltd.