Study of coupling effects in steady-state CANDU core for different operating conditions

Nuclear safety studies often deal with power transient analysis requiring the coupling of neutronic and thermal-hydraulic calculations. However, before considering transient situations, it is necessary to analyze steady state behavior. Hence, the goal of this paper is to present an analysis of steady state coupling effects through a test case simulating the withdrawal of adjuster rod number 11 at different operating conditions. From this study, it is possible to conclude that thermal-hydraulic feedback is a complex phenomenon producing different coupling effects through interacting thermophysical properties. Consequently, not taking into account the neutronic/thermal-hydraulic coupling can result either in underestimating or overestimating a power peak depending on the initial state of the core. (author)