Research interests include filtration, gas-liquid and liquid-liquid coalescence, and nanofibers. Volume averaged continuum theory for multiphase systems are applied to model filters and flows through porous materials. The volume averaged continuum theory provides the same organizational advantages as are available for single-phase systems. Experiments are conducted to provide data for model verification and for applications of research results to specific systems. Other research interests include depth filtration, shale shakers, cross-flow filtration, electrorheological fluid flow through packed beds, and droplet motion on fibers and fiber mats, application of nanofibers in filter media, ceramic fibers for high temperature applications, fiber orientation in filter media, non-Newtonian flows in porous media, and catalytic filter media.