Assessment of the fuel assembly pin-by-pin model in the KORSAR/GP code

Abstract

AbstractThe purpose of this paper is the assessment of the FA pin-by-pin model available in the KORSAR/GP code. The paper presents the results of the simulation of an “Control rod ejection” accident. This accident is of interest due to the power redistribution in the FAs effected by the ejection. The safety margins are calculated with the use of the “hot channel” model for NPP safety analyses. Only the fuel rods of the core with the highest power are taking into account. The absence of the change of the pin power distribution for the FA during the transient is compensated by increased conservatism. In this paper, the maximum fuel rod power was obtained using the pin-by-pin model.