Reynolds Number Effects in Wall-Bounded Turbulent Flows
Abstract
This report reviews the state-of-the-art of Reynolds number effects in wall-bounded shear-flow turbulence, with particular emphasis on the canonical zero-pressure-gradient boundary layer and two-dimensional channel flow problems. The Reynolds numbers encountered in many practical situations are typically orders of magnitude higher than those studied computationally or even experimentally. High Reynolds number research facilities are expensive to build and operate, and the few existing ones are heavily scheduled with mostly developmental work. For wind tunnels, additional complications due to compressibility effects are introduced at high speeds. Full computational simulation of high Reynolds number flows is beyond the reach of current capabilities. Understanding of turbulence and the use of modeling will continue to play vital roles in the computation of high Reynolds number practical flows using the Reynolds-averaged Navier-Stokes equations. Because the existing knowledge base, accumulated mostly through physical as well as numerical experiments, is skewed toward the low Reynolds numbers, the key question in such high Reynolds number modeling in addition to devising novel flow control strategies is: What are the Reynolds number effects on the mean and statistical turbulence quantities and on the organized motions? The coherent structures in low Reynolds number wall-bounded flows have been reviewed several times since the 1960s. However, the Reynolds number effects on the higher order statistical turbulence quantities and on the coherent structures have not been reviewed thus far, and there are some unresolved aspects of the effects on even the mean flow at very high Reynolds numbers. Furthermore, a considerable volume of experimental and full-simulation data has been accumulated since 1962. This report aims at further assimilation of those data, pointing to obvious gaps in the present state of knowledge and highlighting the misunderstood and the ill-understood...
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 18, 1994
- Accession Number
- ADA637054
Entities
People
- M. Gad-el-hak
- P. R. Bandyopadhyay
Organizations
- Naval Undersea Warfare Center