Experimental study of the gas-liquid flow characteristics in a rectangular channel with a large aspect ratio

Abstract

Abstract This paper experimental studies the gas-liquid flow in a rectangular slit microchannel with cross-section of 200 × 2045 μm. Ethanol and nitrogen are used as working liquids and gas, respectively. The microchannel with an internal symmetric hydraulic focusing mixer is used for the study of the flow pattern for elongated bubble and transition flows. For the study of the wave patterns in the liquid film, the microchannel with an external mixer is applied. Experimental data on flow patterns are obtained using high-speed visualization and laser-induced fluorescence (LIF) methods. Using method LIF for elongated bubble and transition flows the local film thickness is measured and compared with Taylor law. For microchannel with an external mixer, the local liquid film thickness is measured for a wavy film at high gas velocity, and the wave influence on local film distribution is discussed.