A New Spherical Harmonics Scheme for Multi-Dimensional Radiation Transport I: Static Matter Configurations

Abstract

Recent work by McClarren & Hauck [32] suggests that the fltered spherical harmonics method represents an effcient, robust, and accurate method for radiation transport, at least in the two-dimensional (2D) case. We extend their work to the three-dimensional (3D) case and fnd that all of the advantages of the fltering approach identifed in 2D are present also in the 3D case. We reformulate the flter operation in a way that is independent of the timestep and of the spatial discretization. We also explore different second- and fourth-order flters and find that the second-order ones yield signifcantly better results. Overall, our findings suggest that the filtered spherical harmonics approach represents a very promising method for 3D radiation transport calculations.