Kinetic parameters study based on burn-up for improving the performance of research reactor equilibrium core

Abstract

In this study kinetic parameters, effective delayed neutron fraction and prompt neutron generation time have been investigated at different burn-up stages for research reactor's equilibrium core utilizing low enriched uranium high density fuel (U3Si2-Al fuel with 4.8 g/cm3 of uranium). Results have been compared with reference operating core of Pakistan research Reactor-1. It was observed that by increasing fuel burn-up, effective delayed neutron fraction is decreased while prompt neutron generation time is increased. However, over all ratio βeff/Λ is decreased with increasing burn-up. Prompt neutron generation time A in the understudy core is lower than reference operating core of reactor at all burn-up steps due to hard spectrum. It is observed that βeff is larger in the understudy core than reference operating core of due to smaller size. Calculations were performed with the help of computer codes WIMSD/4 and CITATION.