Simulation of the Equilibrium Operation of a Candu Reactor and Studies of the Collapsing Procedure in the Fuel Management Design Program

Abstract

Estimates of fuel management data for the equilibrium operation of a specific CANDU reactor have been obtained by simulating a period of the reactor's history using the Fuel Management Design Program (FMDP). The collapsing procedure in FMDP has been tested and improved. This procedure prepares a coarse mesh model of the reactor core from a detailed fine mesh calculation. The program calculates a set of coarse mesh parameters which, when used in the flux calculation, will regenerate exactly the same eigenvalue and flux distribution as the fine mesh model. These parameters can then be used with the coarse mesh, to calculate flux distributions for a series of perturbations from the reference calculation used in collapsing. Several coarse mesh models were generated and studied. It was found that coarse mesh calculations with collapsed parameters result in large savings in computing costs compared to the same calculations with fine mesh, but with very little loss in accuracy.