NUMERICAL PREDICTION OF PHASE-SEPARATION IN 2-PHASE FLOW-THROUGH T-JUNCTIONS

The paper presents a predictive numerical method which solves the full, three-dimensional, two-fluid model equations for dispersed two-phase flow by control-volume discretization. The methodology incorporates general coordinates, indirect-addressing for easy mapping of non-rectangular domains and is based on the use of non-staggered meshes. Turbulence is modelled either by the standard k-epsilon turbulence model or by an extension of that model which accounts for void-fraction fluctuations. The method is applied to air water bubbly flow in a rectangular cross-section T-junction for which experimental data is available. Comparisons of the predictions with measured velocities and phase separation ratios show good agreement. Contours of the volume-fraction reveal the presence of a pocket of high gas concentration at the entrance to the side arm, similar to that actually found in experiments. The effects of interfacial drag model, turbulence model and bubble diameter on the predictions are also investigated.