Prediction of Flow Distribution in Gas-Liquid Two-Phase Annular Flows in a Rod Bundle Under Hydraulically Equilibrium Condition

Subchannel flow distributions of both gas and liquid phases under a hydraulically equilibrium condition have been investigated experimentally and analytically for two-phase annular flows in a vertical channel simulating a BWR fuel rod bundle. In the experiment, data on two-phase flow rates in subchannels were obtained for several equilibrium annular flows. In the analysis, a simple, one dimensional, one pressure, two-fluid model has been applied to calculate the flow distributions. In addition, an equation of identical-wall-shear-stress between subchannels was incorporated as a closure equation for the analysis. From a comparison between the calculation and the experiment, the present analysis was found to be promising.