Flow Structure and Velocity Distribution in Horizontal Gas-Liquid Intermittent Flow Detected by S-PLIF&PIV

Horizontal gas-liquid two-phase flows are prevalent in industrial processes such as petroleum and aerospace fields. Intermittent flow is the most common flow pattern of horizontal gas-liquid two-phase flows. Detecting the flow structure and the velocity distribution in intermittent flow plays a critical role in comprehending the heat/mass transfer characteristics and revealing the flow pattern transition mechanism. In this paper, we designed an optical measurement system, i.e., structured planar laser-induced fluorescence and particle image velocimetry (S-PLIF &PIV), to collect the flow images of plug flow and slug flow during the experiment. A new image processing method was presented to precisely extract the gas-liquid interface and the velocity distribution in the liquid phase. Furthermore, we derived the vortex structure and the axial average velocity profile to analyze the slug aeration characteristics.