Two-Phase Void Drift Phenomena in 2x3 Rod Bundle (Calculation of Flow Redistribution by a Two-Fluid Model)

Abstract

The purpose of this study is to describe analytically two-phase void drift phenomena in a 2×3 rod bundle channel simulating BWR fuel rod bundle. For that, a subchannel analysis code, which was developed by the present authors and based on a two-fluid model, was used, and prediction of gas and liquid flow redistribution due to void drift between subchannels in the 2×3 rod bundle channel was conducted. In the code, a void settling model for evaluating the void drift effect was incorporated with usual conservation equations of mass and momentum. From a comparison, it was found that the subchannel analysis code can predict well the data on subchannel flow and void fraction variations in the 2×3 rod channel if an appropriate correlation was employed to evaluate wall and interfacial friction forces.