One-Dimensional Diffusion Theory Kinetics in RELAP5

A one-dimensional (axial) space-time reactor kinetics capability has been developed for the well-known RELAP5 thermohydraulic systems code for modeling the behavior of nuclear power plants. The method is based on the analytic nodal method with a novel technique for performing the temporal integration over relatively large time steps. Benchmark calculations using the model show excellent agreement with a corresponding analytic solution for a simple one-dimensional model problem.