Experimentally investigating phase separation and pressure drop as bubbly flow in a vertical branching T-junction

Abstract

The majority of this paper investigates the phase separation and pressure drop characteristics for a bubbly flow passing through a vertical branching T-junction. Effects of inlet superficial velocities of both phases and outlet pressure on the efficiency of phase separation in the T-junction are also considered. Based on the experimental results, the liquid separation efficiency increases as the inlet superficial liquid velocity or the outlet pressure at the branch decreases. This trend is similar to the previous works. Phase separation characteristics can be observed using a high-speed camera. A simplified two-phase frictional pressure-drop model is also proposed to estimate the inlet-to-run and the inlet-to-branch frictional pressure drops across the T-junction. Comparison of two-phase frictional pressure-drop shows that the present model can reproduce the data with the deviation of 40%. The predicted frictional pressure drop using the two-phase multiplier of Sun-Mishima correlation is closer to the data than that using the Lockhard-Martinelli correlation.