The dynamics of a single bubble as it grows at and eventually detaches from the tip of submerged capillary orifices in isothermal pools of pure liquids of varying fluid properties is studied experimentally. The transient interfacial behavior around the evolving isolated bubble (from inception through growth, necking, and detachment) is mapped by means of optical micro-scale flow visualization that uses a high-speed high-resolution digital camera and image processing system. Parametric effects of capillary orifice diameter (do = 0.32, 1.0, and 1.76 mm), air flow rate (2 ≤ ≤ 20 ml/min), and liquid properties (surface tension and viscosity), on the bubbling signature (growth time, departure diameter, and bubble interval) are explored and highlighted. It is found that bubble evolution, in a first order scaling, can be correlated by a balance of forces due to buoyancy, viscosity, surface tension, liquid inertia, and gas momentum transport at the transient gas-liquid interface.

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