van den Berg Thomas H, van Gils Dennis P M, Lathrop Daniel P, Lohse Detlef
Department of Applied Physics, IMPACT, and J.M. Burgers Center for Fluid Dynamics, Physics of Fluids Group, University of Twente, P.O. Box 217, 7500 AE Enschede, Netherlands.
Phys Rev Lett. 2007 Feb 23;98(8):084501. doi: 10.1103/PhysRevLett.98.084501. Epub 2007 Feb 21.
In turbulent Taylor-Couette flow, the injection of bubbles reduces the overall drag. On the other hand, rough walls enhance the overall drag. In this work, we inject bubbles into turbulent Taylor-Couette flow with rough walls (with a Reynolds number up to 4 x 10(5), finding an enhancement of the dimensionless drag as compared to the case without bubbles. The dimensional drag is unchanged. As in the rough-wall case no smooth boundary layers can develop, the results demonstrate that bubbly drag reduction is a pure boundary layer effect.
在湍流泰勒-库埃特流中，注入气泡会降低整体阻力。另一方面，粗糙壁面会增大整体阻力。在这项研究中，我们将气泡注入到具有粗糙壁面的湍流泰勒-库埃特流中（雷诺数高达4×10⁵），发现与无气泡的情况相比，无量纲阻力有所增大。有量纲阻力则保持不变。由于在粗糙壁面的情况下不会形成光滑边界层，结果表明气泡减阻是一种纯粹的边界层效应。
