An iterative $\mathrm{KP}_1$ method for solving the transport equation in $\mathrm{3D}$ domains on unstructured grids

A two-step iterative $\mathrm{KP}_1$ method for solving systems of grid equations that approximate the integro-differential transport equation in $\mathrm{3D}$ domains on unstructured grids using nodal $\mathrm{S_N}$ methods is described. Results of testing the efficiency of the proposed method in solving benchmark problems of reactor protection on tetrahedral grids are presented.