Interfacial exchange relations for two-fluid vapor-liquid flow : a simplified regime map approach

Abstract

A simplified approach is described for selection of the constitutive relations for the inter-phase exchange terms in the two-fluid code, THERMIT. The approach used distinguishes between pre-CHF and post-CHF conditions. Interfacial mass, energy and momentum exchange terms are selected and tested against one dimensional measurements for a wide range of mass flow rate, pressure and void fraction conditions. It is concluded that the simplified regime map approach leads to accurate predictions for LWR applications, excluding depressurization events.