On Challenges in Turbulent Flow Theory and Experiment

Research in macroscopic classical physics, such as fluid dynamics or aspects of condensed matter physics, continues to confront baffling challenges that are by no means less demanding than those at the post-Newtonian frontiers of physics that have been explored since the beginning of this century. This is so even though the basic equations of macroscopic classical physics are knownindeed, have been known for centuries in many cases. Chaos and nonlinear dynamics are examples of the topics that pose new challenges to our understanding of macroscopic classical systems. Turbulence, a phenomenon related to but distinct from chaos, and having strong roots in engineering, has been increasingly in the focus of physics research in recent years. Turbulence occurs in a very wide variety of flows, ranging from the mixing of cream in a coffee cup to the dispersal of pollutants in the atmosphere, from the formation of galaxies in the early universe to thermal convection in stars, from flows around automobiles, ships and aircraft to combusting flows in turbomachinery.

Uriel Frisch and Steven A. Orszag, DOI: 10.1063/1.881235