# Identifying coherent structures in fluid flow

Date and Time:

Friday, May 29, 2015 - 16:00

Speaker(s):

Prof. Gary Froyland, School of Mathematics and Statistics, University of South Wales, Sydney, Australia

The future behavior and transport mechanisms of complicated (chaotic or "turbulent") fluid flow is hard to predict. However, in many situations there are regions of predictability embedded in the flow that exhibit approximately regular behavior. These regions of predictability are often bounded by strong transport barriers and evolve as coherent, slightly leaky parcels of fluid. Geophysical examples include polar vortices in the stratosphere and ocean gyres and eddies. I will describe probabilistic (ergodic-theoretic) techniques based on spectral properties of transfer operators to identify these coherent regions, and the application of these techniques to two geophysical examples.

Bio:

Gary Froyland is currently an Australian Research Council Future Fellow and Professor in the School of Mathematics and Statistics at UNSW Australia. He received his PhD in mathematics from the University of Western Australia, and held an Australian Academy of Science Postdoctoral Fellowship at the University of Tokyo. During a break in his academic career, he worked for BHP Billiton, one of the world’s largest resource companies, and was awarded the BHP Billiton Innovation Prize. His research interests cover dynamical systems and discrete optimization. His dynamical systems research focuses on the interplay of probability and geometry in nonlinear and chaotic flows, and uses tools from ergodic theory. In addition to fundamental mathematical research in dynamical systems, he has applied his research methods to analyse oceanic, atmospheric, and granular flows, using models and observational data. His optimization research is focused on decision making in large and complicated systems, sometimes in the presence of uncertain information. His research concerns new modelling approaches in mathematical programming, integer programming, and stochastic programming. These new approaches have been applied to strategic planning of open pit mines, scheduling of maritime crane fleets, and robust scheduling of aircraft and flight crews under uncertain disruption. Current work concerns optimisation of cancer radiotherapy treatments.