Behavior of Wake Flow Behind Obstacle in a Gas-Liquid Vertical Two-Phase Flow. Effects of Blockage Ratio.

An experimental study on the behavior of wake flow behind an obstacle, square cylinder, in a gas -liquid vertical two-phase flow especially the effects of blockage ratio, is examined. The results showed that Karman vortex was shed regularly under certain flow conditions for various Reynolds number, void fractions and blockage ratios. Two uniform experimental equations were shown to describe the vortex shedding frequency f and pressure difference ΔP between the front side and the back side of the obstacle for various blockage ratios. A new measuring method by f and ΔP for the flow rate of gas-liquid two-phase flow was shown.