Education

• Ph.D., Northwestern University, 1982
• M.S., Stanford University, 1977
• B.S., Michigan State University, 1976

Background

Dr. Smith began at Tech in 1991 as an Associate Professor. Prior, he was an Assistant Professor at Johns Hopkins University.

Research

• Fluid Mechanics; Hydrodynamic stability, liquid films,and droplet atomization

Dr. Smith's research interests include theoretical fluid mechanics, hydrodynamic stability, nonlinear stability, surface-tension-driven flows, free-surface flows, contact-line problems, and droplet dynamics. His current research includes the development of new phase-change heat transfer technology, a study of the fluid dynamics of bioreactors, and the behavior of surface-tension-driven flows in thin films and droplets.

To meet the future needs of thermal management and control in space applications such as the Space Lab, new heat transfer technology capable of much larger heat fluxes must be developed. This project (with Dr. Ari Glezer) concerns the fundamental fluid mechanics and heat transfer processes involved in a new, self-contained, heat transfer cell for microgravity applications. The work involves experimental and numerical investigations into the basic physics of the atomization process and the use of this technology in the design of a working heat transfer cell.

Another project (with Drs. G. Paul Neitzel, Robert Nerem, and Timothy Wick) is the fluid dynamics of bioreactors. Bioreactors are vessels in which biological cells may be cultured, to the point that actual tissues may be grown. The fluid-dynamic environment of the bioreactor is crucial to the success of the endeavor. The tissues are fragile and do not survive in high-shear environments, however, convection is necessary to provide nutrients to the cells and to rid the neighborhood of the cultures of waste products. This work will characterize the flow within an existing, rotating-wall bioreactor, examine the response of tissues to varying shear stresses, and redesign the bioreactor to provide a more hospitable environment for tissue growth.

Surface-tension-driven flows are of central concern in a microgravity environment because they can be the dominant flows in some processes used in the space environment. This project considers a thermocapillary flow in a thin film contained in a shallow slot. Asymptotic methods are used to develop a nonlinear equation to describe the behavior of the free surface of this film. The numerical simulations will improve the understanding of how unsteady thermocapillary flows behave in a bounded domain and will help identify the associated instability mechanisms.

In a microgravity environment, there is a need to control and manipulate small and large masses of fluid to ensure that the associated systems behave properly. In a project on thermocapillary droplet migration, Dr. Smith is investigating one technique for microgravity fluid management. The idea is to impose a temperature gradient on a rigid surface to produce a thermocapillary flow in a liquid droplet attached to the surface. The results will help to describe the physics of thermocapillary droplet migration and the extent to which it can be applied successfully in a real microgravity application.

Dr. Smith's work is sponsored by the National Aeronautics and Space Administration.