Event Information
Jerry Gollub (University of Pennsylvania, Haverford College)
Novel Ways of Studying Fluid Flows
- Abstract:
Fluid flows are important in many fields of science, including physics, chemistry, geophysics, biology, and engineering. They have been studied for centuries by observing the behavior of dyes or small particles deposited in the flow. However, the presence of space-time chaos makes it quite hard to understand even relatively slow, non-turbulent flows. The advent of high resolution digital imaging has changed the situation dramatically. One can now track thousands of particles as a function of time to extract high-resolution time-dependent velocity fields, or related fields like vorticity (local rotation). Sometimes the stretching or elongation of fluid elements is important, and this quantity can now also be measured with high space and time resolution. Stretching can give insights into mixing and chemical reactions. Finally, the curvature of fluid elements can be measured, and this capability makes it possible to find special topological features of fluid flows, like elliptic points (local vortices) and hyperbolic points (local saddle or stagnation points). The study of the motions of these special topological points can give insight into the origins of space-time chaos in fluids. In this talk, I will show how advances in flow measurement can give novel insights into fluid motion.
Host: The Duke University Physics and Chemistry Departments
The Duke University Chapter of Sigma Xi
Fritz London Memorial Lecture