Core Radial Profile Effect During Reflooding, Validation of CATHARE2 3D Module Using SCTF Tests

Abstract

CATHARE2 is a best-estimate system code developed (CEA, EDF, AREVA-NP, IRSN) for PWR safety analysis. The 3D module has been developed to ensure a good description of the large scale thermal-hydraulic 3D effects taking place in a PWR vessel, and particularly during the reflooding phase of a large break loss-of-coolant accident. This paper illustrates the CATHARE2 3D module assessment against SCTF forced feed reflood tests (ECC injection in the lower plenum) dealing with radial power profile effect on core cooling, focusing on cladding temperature profiles, upper plenum collapsed water level and quench front progression. These calculations assess the CATHARE2 3D module ability to predict the mixing phenomena and to describe the core radial profile effects. Quench front progression, 2D cross-flows and maximum clad temperatures are well predicted by CATHARE2.