Start
Jan 22, 2015 - 17:00
End
Jan 22, 2015 - 18:00
Venue
LC-102
Event Type
Speaker
Dr. Sumesh Thampi Postdoctoral Research Assistant Dept. of Physics Oxford University
Title
Active Turbulence
Abstract: Dense active systems spontaneously generate turbulent-like flow states where the velocity field is highly disordered with a continually changing pattern of vortices. Examples include mixtures of microtubules and molecular motors (the machinery that acts as a cellular engine or cells themselves) bacteria vibrating granular rods flocks of birds and schools of fish. We model such active systems using continuum theory of an active nematic to show that active turbulence develops in two stages: (i) ordered regions undergo an intrinsic hydrodynamic instability generating lines of strong deformations (ii) the lines relax by forming oppositely charged pairs of topological defects. Defects and distortions in the director field act as sources of vorticity and thus vorticity is strongly correlated to the director field. Topological defects can be continuously created and destroyed in biological systems and it seems that this dynamics underlies the turbulent patterns in active materials.Bio-sketch: Sumesh did his under-graduation in Chemical Engineering from Calicut University and his M.Tech from IIT Kanpur. After a few years of industrial exposure in Larsen & Toubro Limited Mumbai and Reliance Industries Limited Mumbai he joined JNCASR Bangalore for his PhD where he worked on mechanics of drops on solid surfaces. Subsequently he joined the soft matter group in Oxford University for his Post-doctoral work. Presently he is working on continuum models of living systems to understand their physics and thence facilitate the development of micromechanical devices that can exploit biological energy.
Note : Attendance is mandatory for CL702/ CL704 Participants.