Abstract:
Many cells and microorganisms are motile: they are capable of navigating fluid environments to accomplish tasks required for survival or specialized functions. I will describe the physical principles obeyed by swimming at the micro scale and the mathematical models used to describe them. I will present numerical results for a sperm cell-like swimmer in an unbounded domain and compare several models of different fidelity based on the Stokes flow approximation. The models include a Regularised Stokeslet Method, a 3D Finite Element Method, the Resistive Force Theory versions of Lighthill and Gray and Hancock, as well as a simplified approximation based on computing the hydrodynamic forces exerted on the head and the flagellum separately. I will discuss applications that may arise from our ability of modeling and manipulating microswimmers and the challenges that lie ahead.
Biography:
Dr Cecilia Rorai earned her Ph.D. from the Doctoral School in Environmental and Industrial Fluid Mechanics, University of Trieste, Italy. She conducted her doctoral research at University of Maryland in collaboration with Professors D. P. Lathrop, R. M. Kerr and under the supervision of Professors K. R. Sreenivasan and Michael E. Fisher. She defended her thesis entitled “vortex reconnection in superfluid helium” in April 2012. Later, she moved as a visiting scientist at the National Center for Atmospheric Research (NCAR), Boulder, Colorado, where she worked on turbulence in stratified flows in collaboration with Professor Annick Pouquet, Dr D. Rosenberg and Professor P. D. Mininni. In 2013 she joined the Royal Institute of Technology (KTH) and the Nordic Institute of Theoretical Physics (NORDITA) Stockholm, Sweden, as the recipient of the postdoctoral fellowship from the Göran Gustafsson foundation. Her project dealt with the motion of elastic capsules in Stokes flows and involved Professor Luca Brandt, Dr Dhrubaditya Mitra and Dr Lailai Zhu. In 2016 she was awarded a Marie Skłodowska-Curie postdoctoral fellowship and she joined Queen Mary University where she works in collaboration with Dr Sergey Karabasov. Her current research focus is on biological fluid dynamics, more specifically, swimming at the micrometer scale. Her approach is theoretical and computational.