Development of a core protection calculator module for the NSSS transient analyzer based on best-estimate codes for light water reactors

KEPRI and KAERI have jointly developed a CPC (Core Protection Calculator) module as a part of the development project for an NSSS transient analyzer based on the best-estimate system code, RETRAN. To develop the CPC module as an NSSS transient analyzer, a number of code modifications, such as simplifications of text based input and interface with main program using the shared memory technique, were made to satisfy the analyzer requirements. In this paper, the safety analysis is carried out to confirm the feasibility of the CPC module for the loss of forced reactor coolant event of Ulchin unit 3 and 4. The results of the analysis are compared with those mentioned in FSAR and it is concluded that the CPC module shows acceptable trends during transients of the event