This event is in-person and open only to Princeton University ID holders

Transport processes at low Reynolds number are strongly affected by complex geometries and porous environments, which are omnipresent in biological and microfluidic settings. In the first part of this talk, I will address the hydrodynamic interactions between sedimenting particles and nearby surfaces with corrugated topographies. I will present a perturbation theory valid for small surface roughness and derive an integral expression for the roughness-induced mobility. The latter depends on the surface structure, which we model with periodic or random shape functions. I will then discuss the sedimentation behavior of a sphere next to different surfaces and show a comparison of our theory with experiments. In the second part of this talk, I will address the transport behavior of active agents, such as swimming microorganisms or synthetic self-propelled particles. I will discuss the motion of active stiff polymers undergoing run-reverse dynamics, and so mimic bacterial swimming, in porous media. Our study demonstrates that the long-time effective diffusivity of run-reverse agents becomes optimal at an intermediate reversal rate, which we explain by a geometric criterion.

Christina Kurzthaler is a postdoctoral research fellow working with Prof. Howard A. Stone at the Department of Mechanical and Aerospace Engineering at Princeton University. Her research interests encompass the statistical physics and fluid dynamics of soft and active matter systems. She obtained her PhD in Theoretical Physics advised by Prof. Thomas Franosch from the University of Innsbruck and the Master of Science degree in Mathematics in Biosciences from the Technical University of Munich.