An Asymptotic Study of Discretized Transport Equations in the Fokker-Planck Limit

Recent analyses have shown that the Fokker-Planck equation is an asymptotic limit of the transport equation given a forward-peaked scattering kernel satisfying certain constraints. Discretized transport equations in the same limit are studied, both by asymptotic analysis and by numerical testing. It is shown that spatially discretized discrete ordinates transport solutions can be accurate in this limit if and only if the scattering operator is handled in a certain nonstandard way.