Physics Colloquium, October 12, 2004

Flapping, flying and drifting --- free boundaries in moving fluids

Jun Zhang

Department of Physics and Courant Institute, New York University

We study experimentally several fluid projects that are motivated from both biology and geophysics. Those "simple" table-top experiments are intended to answer "big" questions. In this talk, I will first introduce the experiment that investigates the motion of flapping flags, which is closely related to the swimming of fish. We will then discuss how a symmetric, rigid wing generates horizontal thrust and performs a forward flight, when it is flapped vertically (just like a bird). Finally, we examine another fluid experiment that deals with a free boundary which mimics the dynamics of a continent atop the thermal convection motion of the Earth's mantle.

3.30 p.m., Smith Laboratory, Room 1005

Refreshments served in Smith 1094 at 3:00 p.m.