Seminar: Fake Turbulence - Nov. 22
Javier Jiménez
Emeritus Research Professor, Fluid Mechanics, Polytechnic U. Madrid
Friday, Nov. 22 | 10:40 a.m. | AERO 111
Abstract: Turbulence is a high-dimensional dynamical system with known equations of motion. It can be numerically integrated, but the simulation results are also high-dimensional and hard to interpret. ÌýLower-dimensional models are not dynamical systems, because some dynamics is discarded in the projection, and a stochastic Perron-Frobenius operator substitutes the equations of motion. Using as example turbulent flows at moderate but non-trivial Reynolds number, we show that particularly deterministic projections can be identified by either Monte-Carlo or exhaustive testing, and can be interpreted as coherent structures. We also show that they can be used to construct data-driven ‘fake’ models that retain many of the statistical characteristics of the real flow.Ìý
Bio: Aeronautical Engineer by the Madrid School of Aeronautical, and Ph.D. in Applied Mathematics by Caltech. Currently Emeritus research professor of Fluid Mechanics at the Polytechnic U. Madrid. Past positions include the Ec. Polytechnique, Palaiseau, Stanford University, NASA Ames Res. Centre, and the IBM Madrid Scientific Centre. He is member of the Spanish Royal Academy of Sciences and of the Spanish Royal Academy of Engineering. Elected fellow of the American Physical Society, the Institute of Physics of London and of the European Mechanics Society (Euromech). Ìý
He has received the research prize of the Spanish Academy of Sciences and the Fluid Mechanics prizes of both Euromech and the APS. He has coauthored over a hundred publications in international refereed journals, 10 books, 85 book chapters and invited conferences, 13 invited courses, 21 technical reports and numerous other publications, resulting in about 25000 citations. He has directed 19 doctoral theses.