DEPARTMENT OF MATHEMATICAL SCIENCES

APPLIED AND COMPUTATIONAL MATHEMATICS SEMINAR

**Speaker:** Ashwin Vaidya, Mathematics, University of North Carolina, Chapel Hill

**Title: ***
A Mathematical Theory of Fluid-Solid Interaction with Application to Particle Sedimentation
*

**Abstract:**
The interaction of fluids with solids has given rise to some very interesting
mathematical and physical problems on pattern formations, stability and bifurcations. One
can point to applications in a variety of fields such as engineering flow problems and
those in biological systems such as aggregation phenomena of cells in blood flow. We will
look at the simplest version of the general class of such problems; the motion of a
single rigid body immersed in a fluid which can be Newtonian or non-Newtonian. In
particular, we examine the orientational dynamics of a symmetric body moving in a fluid.
Experiments show that the attitude that a particle assumes when immersed in a fluid
depends upon the material properties of the fluid as well as the shape of the body. As
the inertial effects in the fluid increase, vortex shedding in the wake of the body gives
rise to some very interesting dynamics and transitions. In this talk we present an
overview of some mathematical, experimental and numerical work that we have done
regarding this problem.

**Time:** Friday, April 24, 2009, 1:30-2:30 p.m.

**Place:** Science and Tech I, Room 242

Department of Mathematical Sciences

George Mason University

4400 University Drive, MS 3F2

Fairfax, VA 22030-4444

http://math.gmu.edu/

Tel. 703-993-1460, Fax. 703-993-1491