Control at the boundary: experiments and modelling in turbulent flows

Speaker name: Prof. Beverley J. McKeon

Institution: California Institute of Technology, U.S.A.

Curriculum vitae: 

Beverley McKeon is Theodore von Karman Professor of Aeronautics at the Graduate Aerospace Laboratories at Caltech (GALCIT) and the Deputy Chair of the Division of Engineering and Applied Science. Her research interests include the development of resolvent analysis for modeling turbulent flows, interdisciplinary approaches to manipulation of boundary layer flows using morphing surfaces, assimilation of experimental data for efficient low-order flow modelling, and fundamental investigations of wall turbulence at high Reynolds number. She was the recipient of a Vannevar Bush Faculty Fellowship from the U.S. Department of Defense in 2017, the Presidential Early Career Award (PECASE) in 2009 and an NSF CAREER Award in 2008, and is a Fellow of the American Physical Society and the American Institute of Aeronautics and Astronautics. She currently serves as co-lead editor of Physical Review Fluids and is a member of the editorial board of the Annual Review of Fluid Mechanics; she has served in the past as editor-in-chief of Experimental Thermal and Fluid Science and on the editorial boards of the AIAA J. and Experiments in Fluids. She is the Chair, and APS representative, of the US National Committee on Theoretical and Applied Mechanics.

Abstract In this talk I will discuss the effect of control at the wall in turbulent flows. Turbulent boundary layers over rough walls, compliant walls and under opposition control will be examined through experiments, simulation and modeling. In the latter case, resolvent analysis provides a link between the observed flow response and the equations of motion; a dramatic reduction in complexity of these problems can be obtained, associated with sparsity, self-similarity and low-rank behavior in the resolvent (attributable to the information encoded in the turbulent mean field). In this talk, I will synthesize observations and analysis to give insight into the underlying flow physics, to obtain low order representations for modeling, and to distill guidelines for control.

The support of the U.S. Office of Naval Research under grant N00014-17-1-3022 is gratefully acknowledged.