Collaborative Research: Physics of Breakup and Population-Balance Modeling of Oil-Coated Air Bubbles in Strong Turbulence

Many natural and industrial processes rely on the transport of bubbles and droplets through fluids. In some cases, bubbles and droplets are coated by a thin layer of another liquid. This creates bubbles with complex structures that behave differently from ordinary, bare bubbles. These coated bubbles affect processes ranging from oil spill dispersion to targeted drug delivery. Breakup of a coated bubble yields a mixture of smaller coated bubbles, uncoated bubbles, and fine droplets. How liquid coatings change bubble deformation and breakup remains poorly understood. This project will integrate laboratory experiments with advanced computer simulations to probe bubble breakup in detail and develop more accurate predictive models. These models will support advances in drug delivery technologies, improve understanding of oil and gas transport in marine environments, and boost the efficiency of industrial separation processes. The project will offer undergraduates hands on research opportunities and inspire K-12 students through interactive demonstrations on fluid motion, bubbles, and scientific exploration. This award will determine how liquid coatings alter the deformation and breakup of bubbles in turbulent flows and will develop predictive breakup models that account for these effects. The project will combine controlled laboratory experiments and high-fidelity computer simulations in a complementary, cross-validating framework to identify the physical mechanisms governing bubble deformation, breakup frequency, and fragment formation. The study will quantify how coating thickness, fluid material properties, and turbulence intensity influence breakup behavior and the resulting distributions of daughter bubbles and droplets. This data will be used to develop physics-based breakup models that can be incorporated into larger-scale engineering simulations. Developing physically informed models will enable more accurate prediction of daughter bubbles and droplet size distributions, which play a central role in determining mass, momentum, and heat transfer in multiphase systems. The resulting framework will improve the ability to predict and model coated bubbles and droplets across a broad range of environmental, biological, and industrial applications. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.