Two-Phase Flow in Microchannels: The Case of Binary Mixtures

Abstract

Pressure measurements for segmented gas–liquid flows revealed a constant pressure gradient when the gas phase gradually expanded along the channel due to a substantial pressure drop (1500–1600 kPa). The segmented flow was formed by miscible gas and liquid hydrocarbons. A fully saturated liquid (pressurized liquid with dissolved gas) near the bubble point was introduced to the channel. Gas bubbles emerged from the liquid phase due to a reduction in local pressure when the fluid traveled through the channel. The gas phase expanded from nearly 0% up to 70% void fraction as the segmented flow accelerated along the channel. A novel, nonintrusive, in situ pressure measurement was used to accurately determine the pressure profile in the channel. To measure the void fraction and local velocity throughout the channel, a high-speed imaging technique was used. Finally, five different available models were used to describe the experimental results. The models considered the liberation of the gas phase from the saturated liquid as well as the subsequent variations in viscosity using a thermodynamic model.