Producing Three-Dimensional Nodal Coupling Coefficients

Abstract

A full scope simulator for reactor operator training requires a neutron kinetics model which is simple and fast enough to run in real time, but accurate enough that the trainee is unaware of differences between a simulated transient and one on the real plant. A space-time reactor kinetics model has been developed for this purpose using Avery's coupled reactor kinetics approach . This model describes the kinetics of large regions of the reactor, called "nodes", with point-kinetics-like equations. The interaction among nodes is described by "coupling coefficients". These coupling coefficients are computed by solving the diffusion equation by finite difference methods in three dimensions and one or two neutron energy groups. This paper describes the calculation of coupling coefficients for use in Light Water Reactors of both the pressurized (PWR) and boiling (BWR) designs.