Special Pierce Lab Seminar - Dr. Harold Auradou

Recent studies have revealed new and rich phenomena occurring when motile microorganisms are transported by a flow. For instance, bacteria or sperm... are observed to be able to swim against the current (positive rheotaxis) or to drift sideway (negative rheotaxis) and to accumulate on surfaces. In this presentation, we will see that bacteria can also modify the flow and have an influence on the fluid rheology. We will demonstrate that bacteria can completely compensate the fluid friction allowing the fluid to flow with zero dissipation. Finally, we will study the effect of the flow on the accumulation on surfaces. The swimming activity is here also observed to have great and non trivial influence on the evolution of the number of bacteria on the surface with the flow rate.

Harold Auradou is a CNRS researcher since 2001. In 2007, he got his habilitation in physics at the University of Paris Sud and became senior researcher in 2011. His field of expertise is flow in porous media.