MechE Colloquium: Turbulent water surface (and what floats on it)
Event details
| Date | 17.12.2024 |
| Hour | 12:00 › 13:00 |
| Speaker | Prof. Filippo Coletti, Department of Mechanical and Process Engineering, ETH Zurich |
| Location | Online |
| Category | Conferences - Seminars |
| Event Language | English |
Abstract: Turbulent free-surface flows are ubiquitous, including virtually all natural bodies of water. The interaction between the turbulence in the bulk and the surface is crucial to determine the transport properties in terms of mass, momentum, and energy, which play a paramount role in processes ranging from ocean CO2 uptake to marine plastic pollution. Even the seemingly simple case of the non-wavy surface above homogeneous turbulence displays very complex dynamics: on one side, the surface quenches the vertical component of turbulent kinetic energy below; on the other, the bulk turbulence leaves its footprint in the flow field along the surface. Here we address several open questions on the subject, with particular focus on the spatial and temporal scales of motion immediately below and along the free surface. To this end, we investigate various flow configurations in multiple experimental facilities, including grid turbulence in an open channel, homogeneous turbulence in a jet-stirred tank, quasi-two-dimensional motion of liquid layers, and an outdoor meandering stream. The results demonstrate the strong influence of the free-surface boundary condition on the small-scale dynamics, the energy cascade of the different velocity components, and the dispersion and clustering of floating objects.
Biography: Filippo Coletti is Professor of Experimental Fluid Dynamics at ETH Zurich, where he has been since 2020. Previously he was McKnight Land-Grant Associate Professor of Aerospace Engineering & Mechanics at the University of Minnesota, which he joined in 2014. He performed his doctoral studies at the von Karman Institute for Fluid Dynamics and at the University of Stuttgart, where he obtained his PhD in 2010, and was postdoctoral fellow at Stanford University between 2011 and 2013. He received the NSF CAREER award in 2015 and the ERC Consolidator grant in 2022. His research interests focus on multiphase flows, which he studies with a range of experimental approaches and with applications to environmental, biomedical, and industrial problems.
Biography: Filippo Coletti is Professor of Experimental Fluid Dynamics at ETH Zurich, where he has been since 2020. Previously he was McKnight Land-Grant Associate Professor of Aerospace Engineering & Mechanics at the University of Minnesota, which he joined in 2014. He performed his doctoral studies at the von Karman Institute for Fluid Dynamics and at the University of Stuttgart, where he obtained his PhD in 2010, and was postdoctoral fellow at Stanford University between 2011 and 2013. He received the NSF CAREER award in 2015 and the ERC Consolidator grant in 2022. His research interests focus on multiphase flows, which he studies with a range of experimental approaches and with applications to environmental, biomedical, and industrial problems.
Practical information
- General public
- Free