报告题目👱：Turbulent Rayleigh-Bénard and Taylor-Couette flow

报 告 人：Prof. Detlef Lohse

University of Twente, the Netherlands

报告时间：Apr.21th (Thursday) 2:30pm-3:30pm

报告地点🏃‍♂️‍➡️：Lecture Hall, Department of Thermal Engineering

报告摘要🤼‍♂️：

Rayleigh-Bénard flow — the flow in a box heated from below and cooled from above — and Taylor-Couette flow -- the flow between two coaxial co- or counter-rotating cylinders -- are the two paradigmatic systems in physics of fluids and many new concepts have been tested with them. They are mathematically well described, namely by the Navier-Stokes equations and the respective boundary conditions.

While the low Reynolds number regime (i.e., weakly driven systems) has been very well explored in the '80s and '90s of the last century, in the fully turbulent regime major research activity only developed in the last decade. This was also possible thanks to the advancement of computational power and improved algorithms and nowadays numerical simulations of such systems can even be done in the so-called ultimate regime of turbulence, in which even the boundary layers become turbulent. In this talk we review this recen progress in our understanding of fully developed Rayleigh-Bénard and Taylor-Couette turbulence, from the experimental, theoretical, and numerical point of view, focusing on the latter. We will explain the parameter dependences of the global transport properties of the flow and the local flow organisation, including velocity profiles and boundary layers, which are closely connected to the global properties. Next, we will discuss transitions between different (turbulent) flow states.

报告人介绍👩🏻‍🦼：

Detlef Lohse graduated from the University of Bonn in 1989 with a degree in Physics, and completed his PhD at the University of Marburg in 1992. He served as a postdoctoral research fellow at the University of Chicago from 1993 to 1995, and was appointed as the chair of Physics of Fluids at the University of Twente in 1998. Detlef Lohse is the “University Distinguished Professor” at University of Twente.

Lohse’s present research interests include turbulence and multiphase flow, granular matter, and micro- and nanofluidics. Lohse’s two most important scientific achievements are his contributions to the explanation of single-bubble sonoluminescence and to a better understanding of thermally driven turbulence. For these achievements he received the Spinoza Prize in 2005, the most prestigious award in science in the Netherlands. In 2009 he has received the Simon-Stevin Master Prize for his work on inkjet printing. He is the recipient of the inaugural, and the most prestigious fluid mechanics prize, the Batchelor Prize, in 2012, for best research in fluid mechanics in the last ten years. He is a member of the German Academy of Sciences, and a member of the Royal Dutch Academy of Sciences. He has published about 400 publications in refereed scientific journals, including 10 Nature/Science papers, 66 Physical Review Letters, 53 Journal of Fluid Mechanics, 47 Physics of Fluids, 6 PNAS, 3 Reviews of Modern Physics, 2 Annual Reviews of Fluid Mechanics.