A coupling of kinetics model with MELCOR code and ATWS analysis

Major purpose of the report is to develop a reactor kinetics model for analyzing the ATWS (Anticipated Transients Without Scram) which is one of severe accident initiating events, and to establish a coupling technology of the developed module with a large computer code for severe accident analysis. For this, a point kinetics module, PKINETIC, has been developed as a stand-alone code whose reference model is selected from the investigation of reactor kinetics models in the current accident analysis codes. In the next step, the MELCOR-PK code has been developed via coupling PKINETIC with the MELCOR (1.8.3) code interconnecting several thermal hydraulic parameters between two codes. In the mean time, the Chexal-Layman correlation in the current MELCOR, which was developed under a BWR condition, is appeared to be inappropriate for a PWR. The PKINETIC module and the MELCOR-PK are compared and verified with a RETRAN calculation. Also, MELCOR-PK is used to analyze the ATWS initiated by a TLOF (Total Loss of Feedwater) transient. (author). 9 refs., 61 tabs., 22 figs