Two-phase flow across a partially damaged core during the reflood phase of a loca

Abstract This study focuses on thermal-hydraulic simulations, at sub-channel scale, of a damaged PWR reactor core during a Loss Of Coolant Accident (LOCA). The aim of this study is to simulate the thermal-hydraulics to provide the thermal-mechanical code DRACCAR with an accurate wall heat transfer law. This latter code is developed by the Institut de Radioprotection et de Surete Nucleaire (IRSN) to evaluate the thermics and deformations of fuel assemblies within the core. The present paper first describes the use of CFD to perform analysis at sub-channel scale. Then we study the capabilities of existing codes CATHARE-3 and CESAR to simulate dispersed droplet flows.

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