Parallel Iterative and Direct Methods for Transport Calculations on Unstructured Grids

Two alternative approaches to the solution of discrete ordinate transport are considered in the context of general unstructured grids. The more traditional approach considered is the solution of a lower triangular system of equations for the spatial intensity distribution. Alternatively, the iterative solution of the system of equations arising from a more general diierencing stencil is also considered. Advantages and disadvantages are considered for both sequential implementation and for spatial domain based parallelism.