DISCRETE ORDINATE MAPPING ALGORITHM FOR REGION-BASED QUADRATURE SETS

Frequently in the solution of problems using the discrete ordinates method, it would be convenient to use different quadrature sets in different spatial regions of the problem. For example, when a problem has a highly diffusive region bounding a void region, using a finer quadrature set in the void region would reduce the occurrence of ray effects in the void region. In this paper, we present a method for mapping between quadrature set regions while conserving current on the boundary between regions. We also present an example problem showing that our linear mapping routine accurately captures the streaming of particles between two quadrature set regions, and that the application of flux factors conserves current at the region boundary.