Filippo Coletti

Free-surface turbulence determines transport properties at the global scale, e.g., the uptake of CO₂ and the spreading of floating plastics in oceans, rivers, and lakes. Even in the seemingly simple case of a flat surface, the dynamics are deceptively complex. In the presence of large surface deformations, the problem is complicated by the mutual transfer of energy between the bulk flow and gravity-capillary waves. The mechanisms by which wind builds waves and their exchange of energy with the underlying turbulence are even less understood. In this talk, I will touch upon fundamental aspects of free-surface turbulence, ranging from cases in which the bulk flow barely deforms the surface; to cases where it corrugates it dynamically; to cases in which turbulence is created and modulated by wind shear and wind-driven waves on the edge of breaking. Those flows are investigated with a suite of experimental facilities and leveraging high-resolution imaging, to improve our predictive understanding of the two-way coupling between the surface and the turbulence underneath.

Biography

Filippo Coletti is Professor of Experimental Fluid Dynamics at ETH Zurich, where he has been since 2020. Previously he was McKnight Land-Grant Professor of Aerospace Engineering & Mechanics at the University of Minnesota, which he joined in 2014. He was visiting professor in IMFT Toulouse and ENS Lyon. He received the NSF CAREER award in 2015 and the ERC Consolidator grant in 2022. He serves in the advisory committee of several international conferences (Turbulence and Shear Flow Phenomena, Lisbon Symposium on Laser & Imaging Techniques in Fluid Mechanics, International Conference of Multiphase Flows) and plays active roles in the Division of Fluid Dynamics of the American Physical Society. He founded and co-organizes the Fluid Mechanics Tour of the Alps, an itinerant seminar series featuring the world’s top fluid mechanicians. His research is focused on turbulent multiphase flows using a range of experimental approaches.