Philip J W Roberts - Bruce Podwal Seminar Series

Bruce Podwal Seminar Series

Application of Fluid Mechanics to Environmental Problems


Philip J. W. Roberts

Professor Emeritus, School of Civil and Environmental Engineering,

Georgia Institute of Technology


12 – 1 pm, Tuesday, November 6, 2018

Civil Engineering Department, Room 115, Steinman Hall


Absract:  Fluid mechanics often plays a major role in mitigating environmental problems. Laboratory experimental techniques to elucidate turbulent mixing, particularly of buoyancy-modified flows, have advanced rapidly in recent years, especially the use of laser-induced fluorescence (LIF). We can now image complex flows at high resolution in three dimensions (3DLIF). This can lead to greatly improved mathematical models of mixing and water quality. In this talk, I will give examples of the application of 3DLIF to the design of diffusers to discharge wastewaters such as domestic effluent and brine resulting from seawater desalination into coastal waters and to improving mixing in water storage tanks. I will also show some examples of the use of hydrodynamic mathematical models to the prediction of wastewater transport in coastal waters in Buenos Aires, San Francisco, and Hawaii, and their interaction with the extensive oceanographic data that it is now possible to collect.

Biography: Dr. Roberts is Emeritus Professor of Civil and Environmental Engineering at the Georgia Institute of Technology. His professional interests are in environmental fluid mechanics, particularly the fluid mechanics of outfall diffuser mixing and the development and application of mathematical models of wastewater fate and transport.  He has extensive international experience in marine wastewater disposal including the design of ocean outfalls, review of disposal schemes, numerical modeling, and the design and analysis of oceanographic field study programs.  Dr. Roberts has lectured widely on outfall design and is presently Co-Chairman of the IAHR/IWA Committee on Marine Outfall Systems.

Dr. Roberts’ mathematical models and methods have been adopted by the U.S. EPA and are widely used around the world.  He is a regular lecturer at workshops for the U.S. EPA on mixing zone analyses and on the use of mathematical models and outfall design for the Pan American Health Organization.  He has developed innovative experimental techniques for research on diffuser mixing processes using three-dimensional laser-induced fluorescence and has published extensively in this area.  For this research he was awarded the Collingwood Prize of ASCE in 1980 and was UPS Foundation Visiting Professor at Stanford University in 1993-94.  He was one of only two Distinguished Scholars in the National Ocean and Atmospheric Administration (NOAA) Oceans and Human Health Initiative (OHHI) where he conducted research on the hydrodynamic aspects of bacterial and pathogen transport in coastal waters.