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A large number of industries use fossil fuels for the purpose of cooling and lubrication utilizing a gas stream that acts as a shearing force on the liquid surface. Decreasing the carbon footprint of these processes needs an improved understanding of the effect of liquid properties. To this end this study investigates experimentally the effect of varying surface tension and liquid viscosity on the bubble generation and film statistics in a gas-sheared liquid flow. The experiments were conducted in a horizontal rectangular channel using high speed imaging in conjunction with the Brightness-Based Laser-induced Fluorescence technique (BBLIF) to measure film thickness over an area with a spatial resolution of 40 μ m and a temporal resolution of 10 kHz. Two butanol–water solutions were used to give reduced surface tensions (namely 0.049 N/m and 0.04 N/m) compared to our previously-studied water only value. Also, two …