The persistence of viscous effects in the overlap region, and the mean velocity in turbulent pipe and channel flows
| dc.creator | Sreenivasan, Katepalli R. | |
| dc.creator | Sahay, Anupam | |
| dc.date | 1997-08-13 | |
| dc.date.accessioned | 2026-07-07T09:16:20Z | |
| dc.date.available | 2026-07-07T09:16:20Z | |
| dc.description | We argue that important elements of the dynamics of wall-bounded flows reside at the wall-normal position $y_p^+$ corresponding to the peak of the Reynolds shear stress. Specializing to pipe and channel flows, we show that the mean momentum balance in the neighborhood of $y_p^+$ is distinct in character from those in the classical inner and outer layers. We revisit empirical data to confirm that $y_p^+ = O(R^{1/2})$ and show that, in a neighborhood of order $R^{1/2}$ around $y_p^+$, only the viscous effects balance pressure-gradient terms. Here, R is the Reynolds number based on friction velocity and pipe radius (or channel half-width). This observation provides a mechanism by which viscous effects play an important role in regions traditionally thought to be inviscid or inertial; in particular, it throws doubt on the validity of the classical matching principle. Even so, it is shown that the classical semi-logarithmic behavior for the mean velocity distribution can be a useful approximation. It is argued that the recently advanced power-law profiles possess a rich underlying structure, and could be good approximations to the data over an extended region (but they too are unlikely to be exact). | |
| dc.description | 15 pages, Latex, 7 eps figures, label positions will need adjustment if the text height or width is changed. To appear in `Self-Sustaining Mechanisms of Wall Turbulence', ed. R. L. Panton, Comp. Mech. Pub., 1997 | |
| dc.identifier | https://arxiv.org/abs/physics/9708016 | |
| dc.identifier | http://arxiv.org/abs/physics/9708016 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/153321 | |
| dc.subject | Fluid Dynamics | |
| dc.subject | Chaotic Dynamics | |
| dc.subject | Statistical Mechanics | |
| dc.title | The persistence of viscous effects in the overlap region, and the mean velocity in turbulent pipe and channel flows | |
| dc.type | text |