The ability to control fluid flow behaviors can lead to quiet, economical, and efficient systems in fluid mechanics and aerodynamics. Because of high dimensionality, strong nonlinearity, and complexity in fluid physics, design of effective control strategies can be challenging. My research focuses on uncovering underlying physics of complex fluid flows using the cutting-edge technique of modal analysis, such as dynamic mode decomposition, global stability analysis, and resolvent analysis. The insights obtained from these analyses provide guidance for physics-driven control designs. In this talk, global stability analysis, resolvent analysis, and modal decomposition methods are adopted to guide parameter selection for open-loop control aiming at (1) suppressing fluctuations in flows over long rectangular cavities; and (2) reducing strength of wingtip trailing vortices. Modal analysis also makes closed-loop control design possible for complex fluid flow problems. A study of suppressing laminar-to-turbulent transition in a channel flow using feedback control will also be discussed. Controller performance and physical control mechanisms are further investigated using high-fidelity numerical simulations.
About the Speaker
Dr. Yiyang Sun is an Assistant Professor in the Department of Mechanical and Aerospace Engineering at Syracuse University. Prior to joining Syracuse University, Dr. Sun was a Postdoctoral Associate in the Department of Aerospace Engineering and Mechanics at the University of Minnesota, Twin Cities. She earned her Ph.D. degree in Mechanical Engineering from Florida State University in 2017, and her B.S. degree in Naval Architecture and Ocean Engineering from Huazhong University of Science and Technology in 2012. Her research interests focus on understanding the underlying physics of fluid flows and designing physics-driven control strategies using computational fluid dynamics and modal analysis.
Host: Professor Andres Goza