A solution of the neutron diffusion equation for a hemisphere with mixed boundary conditions

摘要

An analytic solution of the diffusion equation for a hemisphere of fissile material is presented with mixed boundary conditions. This allows one to study the bare hemisphere with radiation boundary conditions and also the interaction between two hemispheres with opposing flat faces. Numerical results are given for one-speed fast neutrons in ~(235)U. We also develop the procedure for multigroup calculations.