CANDU6 PCR evaluation with a detailed 3-D Monte Carlo analysis

Abstract

In the original CANDU6 design, the PCR was evaluated to be clearly negative. However, the latest physics design tool predicts that PCR is slightly positive for a wide range of reactor power. In this work, the CANDU6 PCR is re-evaluated by a detailed 3-D CANDU6 core model using Monte Carlo code Serpent2 with considering two thermal hydraulic models, at design and operating condition. The Doppler broadening rejection correction method was implemented in the Serpent2 code to take into account thermal motion of uranium nucleus. It is found that the CANDU6 PCR can be clearly negative at low power range for both design and operating conditions.