An Analysis of the Lateral Void Transfer Mechanisms in the ASSERT Subchannel Code

Abstract

An experimental program is underway at Institut de Genie Energetique of Ecole Polytechnique de Montreal to generate a data base of experimental results to be used by the Canadian Nuclear Industry for the verification of the hydraulic models used in subchannel analysis codes. To this end, there is an adiabatic air-water test facility at IGE on which experiments are carried out to determine the void fraction distribution, mass flow rate, crossflow and pressure drops along interconnected subchannels. In this paper we describe the experimental facility as well as presenting typical results for some experiments. The subchannel code ASSERT [I] developed by Atomic Energy of Canada Limited, has been used to model the experiments presented in the experimental section of this paper. Specific attention has been paid to the mechanisms involved in the lateral void transfer. The ability of Assert to model these mechanisms is investigated and discussed.