Neutron Flux Analysis for Power Reactor Instrumentation Design

Abstract

This Senior Individualized Project has been a first step theoretical analysis in an ongoing design engineering project conducted at the Nuclear Energy Division of the General Electric Company. A proposed "neutron window," a solid zirconium enclosure for the in-core instrumentation for the boiling water reactor, was simulated, using two-group diffusion theory applied to three materials in a two-dimensional mixed geometry. The analysis involved development of a computer routine, using relaxation methods, on the H-6000 time-share facility. The "neutron window" feature was found to induce a low and flattened thermal neutron flux distribution in the instrument location, thus providing for improved measurement accuracy and increased detector life expectancy.