Ganapathisubramani, Bharathram (2018) Law-of-the-wall for small-scale streamwise turbulence intensity in high-Reynolds-number turbulent boundary layers. Physical Review Fluids, 3, [104607]. (doi:10.1103/PhysRevFluids.3.104607).
Abstract
Following the dimensional analysis approach carried out in previous studies, it is hypothesized that the small-scale fluctuations should only depend on the inner scales, analogous to the Prandtl's law-of-the-wall for the mean flow. This allows us to examine the high frequency regime of the streamwise energy spectra where a "law-of-the-wall" in spectra would hold. Observations in high-
Reynolds-number turbulent boundary layer data indicate that a conservative estimate for the start of this law-of-the-wall is f+ = 0.005 (which corresponds to 200 viscous time-units) across a range of wall-normal positions and Reynolds numbers. This is sufficient to capture the energetic viscous-scaled motions such as the near-wall streaks, which has a time scale of approximately 100 viscous
units. This spectral collapse is consistent with the observations in internal
flows and external flows in other studies. Furthermore, the spectral collapse leads to a universal scaling (based on skin-friction velocity and kinematic viscosity) for the small-scale streamwise turbulence variance (consistent with the hypothesis) across the entire boundary layer. A logarithmic variation of this
small-scale variance is observed farther away from the wall.
More information
Identifiers
Catalogue record
Export record
Altmetrics
Contributors
University divisions
- Current Faculties > Faculty of Engineering and Physical Sciences > School of Engineering > Aeronautical and Astronautical Engineering
Aeronautical and Astronautical Engineering - Faculties (pre 2018 reorg) > Faculty of Engineering and the Environment (pre 2018 reorg) > Southampton Marine & Maritime Institute (pre 2018 reorg)
- Faculties (pre 2018 reorg) > Faculty of Natural and Environmental Sciences (pre 2018 reorg) > Institute for Life Sciences (pre 2018 reorg)
Current Faculties > Faculty of Environmental and Life Sciences > Institute for Life Sciences > Institute for Life Sciences (pre 2018 reorg)
Institute for Life Sciences > Institute for Life Sciences (pre 2018 reorg)
Download statistics
Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.