Study on the control rod interaction effect in RSG gas multipurpose reactor (MPR-30)

The control rod interaction effect of RSG gas (MPR-30) typical working core was studied using a method based on the exact perturbation theory with three simplifying assumptions, which require only N+1 criticality calculations. The interaction effect between two interacting rods reached up to 19% while the interaction effect of multiple interacting rods reached up to 32% for all (8) control rods involved. The accuracy of the adopted method was extensively investigated to determine the error sources and the magnitude of the error. Through comparison of the present results with ones of the simple summation method, it was obvious that the adopted method was superior in that a significant improvement on the accuracy of the calculated reactivity worth can be achieved with a small number of criticality calculations.