Local characteristics of two-phase gas-liquid flow in a microchannel downstream of T-shaped mixer

Two-phase gas-liquid flow in microchannels occurs in a variety of modern industrial applications. This paper presents the experimental results for the horizontal flow of liquids with different viscosity and gas nitrogen in two microchannels with rectangular cross-sections of 400×210 μm and 395×205 μm with T-shaped mixers. The experiments were conducted using the laser-scanning method, the high-speed video recording, and the laser-induced fluorescence. It was observed that elongated bubble flow, transition flow, and annular flow are the main flow patterns for a rectangular microchannel with a hydraulic diameter substantially less than the capillary constant. The flow pattern map was obtained for distilled water-nitrogen, 25% mass aqueous solution of glycerol -nitrogen, 40% mass aqueous solution of glycerol -nitrogen mixtures in a wide range of liquid and gas flow rates. Statistical characteristics of gas-liquid flow and distributions of the liquid film thickness in cross section of the microchannel were defined. The non-uniform liquid film thickness was experimentally observed at the channel cross-section. The statistical characteristics were determined for the flow of ethanol-nitrogen mixture. It was found that most of the liquid flow in the meniscus on the microchannel short side for the present gas and liquid flow rates.