Squinting at Complex Flows
Hussein Aluie, Department of Mechanical Engineering, University of Rochester
Friday, September 27, 2019
Can you glean insight into complex flows by taking off your eyeglasses and squinting? Flows in nature and in engineering are often complex, forced by external agents, boundary stresses, and internal instabilities, and pervaded by multiscale structures such as eddies, plumes, jets, waves, and turbulence ---spanning many orders of magnitude in size. The nonlinear nature of the dynamics implies a coupling between these multiple scales, which often plays a major role in determining mean-flow evolution and is a primary factor limiting our predictive modeling capabilities. To tackle this class of problems in fluid dynamics, I will present a novel framework we have been developing that is equivalent to taking off your eyeglasses. It is rooted in commonly used techniques in the subjects of PDEs in mathematics, Renormalization Group in physics, and Large Eddy Simulation modeling in engineering.
The approach is very general and allows for resolving nonlinear processes at any scale and at any location in the flow. It relies on a synergistic interplay between rigorous mathematics, physical insight, and numerical computations to probe large data sets from experiments, simulations, and satellite observations. I will discuss the application of this methodology to oceanic, plasma, and compressible flows.