This project will develop a realistic model, based on extensive experiments with 2-dimensional and 3-dimensional foams, to describe liquid foam coarsening and draining. Optimal industrial application of foam can only be achieved wen these two phenomena are properly understood. Current theories, developed for unrealistic motionless and/or ideal dry foams, omit the important interdependence of coarsening and drainage and local dynamic effects, like interfacial elasticity, viscous dissipation, surfactant transport, film rupture, bulk bubble motion/rearrangements, etc. The Magnetic Resonance Imaging (MRI) facility at the University of Notre Dame offers a non-invasive, high-resolution imaging technique for large (>200 bubbles) domain of 3D foam. MRI will provide complete information about global changes in foam structure in experiments on drained/stabilized foam coarsening and wetting front propagation. Experiments on flowing 2D, bi-disperse foam and drainage from a single soap film will capture local film and vertex dynamics. Acquired data will be integrated into a dynamic foam model that will be used to correlate 3D coarsening and wetting front dynamics imaged by MRI. Graduate students involved in the project will receive training in physics and fluid mechanics and will get hands-on experience with MRI. Due to MRI's broad medical, scientific and engineering applicability, this training will prepare them for a range of careers in academia or industry. %%% Many technological processes, like secondary oil recovery, control of polluted ground water, industrial filtration, separation, etc. exploit foam stability and mechanical/transport properties which are strong functions of foam spatial patterns. As a result, optima industrial application can only be achieved when texture coarsening and drainage of liquid foams, which fundamentally changes their spatial patterns, are properly understood. Current theories, developed for unrealistic motionless and/or ideal dry foams, omit the interdependence of these phenomena. The aim of this project is to develop a realistic model, based on extensive experiments with 2-dimensional and 3-dimensional foams, that captures local film dynamic effects on global coarsening and drainage. The Magnetic Resonance Imaging (MRI) facility at the University of Notre Dame offers a non-invasive imagin technique sfor a large domain of 3D foams. Upon successful completion of the research project, the foam models will be disseminated to the scientific community and to the chemical/petroleum industry via the principal investigators websites and through a workshop/conference at the University of Notre Dame. Graduate students involved in the project will receive training in physics and fluid mechanics and will get hands-on experience with MRI. Due to MRI's broad medical, scientific and engineering applicability, this training will prepare them for a range of careers in academia or industry.
