Experimental Study of System Behavior during Reflood Phase of PWR-LOCA Using CCTF

Abstract

A study of a cylindrical core test facility (CCTF) test was performed for modeling the system behavior during the reflood phase of a PWR-LOCA and the following conclu-sions were obtained:
(1) With the exception of some points, the observed phenomena are similar to a model derived from an evaluation model for a PWR safety evaluation.
(2) The different points are the water accumulation in the upper plenum, the ECC bypass in the downcomer, the reduction of the effective downcomer head and the pressure drop at the broken cold leg nozzle and in the inter-connected pipes.