An Efficient Algorithm for Nodal-Transport Solutions in Multidimensional Geometry

An algorithm is derived for implementing nodal-transport methods in multidimensional geometries more efficiently than with current algorithms. The cellwise storage and computational penalties of the nodal methods are reduced significantly. Central processing unit time is reduced two to four times over the direct nodal algorithm with a constant surface-flux approximation, and the number of coefficients required is reduced twofold. The corresponding reductions are even greater when the new algorithm is utilized in the linear surface flux nodal method. Results of testing in two- and three-dimensional rectangular geometry are presented.