Prediction models of void fraction and pressure drop for gas-liquid slug flow in microchannels

The void fraction and pressure drop of gas-liquid slug flow in a circular microchannel were measured using a high-speed video camera and image processing method. Water and two types of glycerol-water solutions were used as the liquid phase, and N2 gas was used as the gas phase. Four microchannels with different diameters (200, 320, 500, and 700 μm) were used. The measured data were compared with the existing and newly developed models. The following conclusions were obtained: (1) the pressure drop was predicted using the model proposed by Warnier et al. (2010) with the liquid film thickness model proposed by Han and Shikazono (2009) within ±20%, (2) a distribution parameter model developed in this study can predict the distribution parameter within ±10% and is more reliable than the other models.