CAM Colloquium: Qiqi Wang (MIT) - Computational Sensitivity Analysis of Chaotic Simulations

Friday, October 13, 2017 at 3:30pm

Frank H. T. Rhodes Hall, 655

Studying computational simulations as dynamical systems have many scientific engineering applications. In this talk, we investigate how a chaotic dynamical system responds to small perturbations. When the dynamical system is a computational simulation, these perturbations can be design changes, environmental noise, numerical error, and modeling uncertainties. We show that many classic concepts and methods for sensitivity and stability analysis do not apply to long time averaged quantities of interest in the presence of chaos. We introduce concepts and techniques applicable to chaotic flows, including Lyapunov spectrum analysis and least squares shadowing method. We demonstrate applications of these concepts and technology and illustrate remaining open questions.

Qiqi Wang got his BS in mathematics from University of Science and Technology at Hefei, China. He then got his Ph.D. in Computational and Mathematical Engineering at Stanford, under the supervision of Parviz Moin and Gianluca Iaccarino. From 2009 to 2015, Qiqi was an assistant professor of Aeronautics and Astronautics at MIT. Since 2015, he has been an associate professor in the same department.

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