Effect of Branch Orientation on Annular Two-Phase Flow in T-Junctions

Experimental data on dividing steam-water two-phase annular flow in T-junctions with horizontal inlet and downwardly inclined branches were obtained. The experiments were performed under experimental conditions which have not been examined before. The branch orientation was found to be a significant parameter affecting phase redistribution in the junction. Increasing the downward inclination of the branch was found to reduce the degree of phase separation in the junction under the present test conditions. This is caused by the nonuniform distribution of the liquid film thickness associated with the horizontal inlet annular flow. The phase redistribution data were compared with available models. The need for additional modelling studies was evident. The pressure changes of two-phase flow in the junction were closely correlated with the phase redistribution phenomenon. The data on pressure changes in the junction were correlated using simple models based on momentum and mechanical energy balances.