Charles Meneveau
Department of Mechanical Engineering
Johns Hopkins University

Friday, April. 18th at 3:00pm
MEK 3550

ABSTRACT: Large Eddy Simulation (LES) of turbulent flows relies on subgrid-scale models as well as wall models. The latter are crucial to LES of wall-bounded flows that do not use sufficiently fine resolution to capture the viscous or roughness sublayer physics. Traditional approaches rely heavily on the notion of equilibrium turbulence physics, or more specifically, Monin Obukov Similarity Theory (MOST) in atmospheric boundary layer applications. For applications to turbulent flow over rough surfaces, the equilibrium wall model has been applied to a wide variety of flows, ranging from LES of flows in wind farms, wind over ocean waves, to boundary layers developing on bio-fouled ship hulls. An enduring problem has been how to characterize the effects of roughness on the flow, typically through an equivalent sand-grain (ks) or roughness (z0) scale. We will discuss a new physics-based approach, the wind-shade roughness model, to determine these roughness length parameters from purely geometric (topographical) information about the surface. We also discuss a generalization of the approach to model the effects of waves for air-sea interactions, a topic of importance to flow modeling in off-shore wind energy applications, among others. We then return to the basic assumption of equilibrium and discuss a method to include non-equilibrium effects, such as rapid temporal changes, based on generalization of the von Karman boundary layer integral method to LES wall modeling. This work is funded by NSF and ONR.

BIO: Charles Meneveau is the Louis M. Sardella Professor in the Department of Mechanical Engineering, is Associate Director of the Institute for Data Intensive Engineering and Science (IDIES) and is jointly appointed as Professor in the Department of Physics and Astronomy at Johns Hopkins University. He received his B.S. degree in Mechanical Engineering from the Universidad Técnica Federico Santa María in Valparaíso, Chile, in 1985 and M.S, M.Phil. and Ph.D. degrees from Yale University in 1987, 1988 and 1989, respectively. During 1989-1990 he was a postdoctoral fellow at the Center for Turbulence Research at Stanford. He has been on the Johns Hopkins faculty since 1990. His area of research is focused on understanding and modeling hydrodynamic turbulence, and complexity in fluid mechanics in general. He is Deputy Editor of the Journal of Fluid Mechanics and has served as the Editor-in-Chief of the Journal of Turbulence. Professor Meneveau is a member of the US National Academy of Engineering, a foreign corresponding member of the Chilean Academy of Sciences, a Fellow of APS, ASME, AMS and recipient of the 2024 Batchelor Prize in Fluid Mechanics, the 2021 Fluid Dynamics Award from the AIAA, the Stanley Corrsin Award from the APS, the JHU Alumni Association’s Excellence in Teaching Award, and the APS’ François N. Frenkiel Award for Fluid Mechanics.