The dynamics of bursting droplets from surface bubbles is an important mechanism for water-to-air transport of small particles and contaminants. We investigated bubble-bursting droplets from bubble plumes, released from an air stone (AS) or a single nozzle (SN) at four gas flow rates ranging from 0.1 to 0.8 L min−1. Quantitative imaging was used to analyze the statistics of size and velocity distributions for rising bubbles and droplets ejected by bursting bubbles. Significantly greater droplet number, mass flow rate, and median size were observed in AS, by factors of 20, 8.6, and 1.8 compared to SN, reflecting the influence of subsurface bubble characteristics on droplet production. Log-normal distributions fit well to droplet size and velocity distribution regardless of the release mechanism. The characteristic median sizes show a bubble–droplet relationship of , which implies Bond number relationship of under constant fluid properties. Scaling analysis using visco-capillary length and capillary velocity shows , suggesting a universal scaling relationship for bursting droplets from surfacing of single bubble and bubble plumes. Involving both length and velocity scales of bubbles and droplets shows , a scaling relationship potentially used for predicting droplet dynamics from bursting bubble plumes. These findings provide the first quantitative scaling linking bubble plume and bursting droplet dynamics, with potential applications in aerosol generation, wastewater aeration, and ocean–atmosphere mass-exchange studies.
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