Prediction of Boiling-Induced Natural Circulation Flow in an Inclined Channel with Non-Uniform Flow Area

Abstract

The boiling-induced natural circulation flow in the engineered cooling channel is modelled and solved by considering the conservation of mass, momentum and energy in the two-phase mixture, along with the two-phase friction drop and void fraction. The model has been applied to estimate the induced mass flow rates through a uniform and non-uniform annular gap between the reactor vessel and insulation under the IVR-ERVC conditions, and also the engineeredcorium cooling system of an ex-vessel core catcher during a severe accident for various system parameters including the channel gap size, inlet diameter, inlet subcooling, and wall heat flux.