- Title
- Towards local isotropy of higher-order statistics in the intermediate wake
- Creator
- Tang, S. L.; Antonia, R. A.; Danaila, L.; Djenidi, L.; Zhou, T.; Zhou, Y.
- Relation
- ARC
- Relation
- Experiments in Fluids Vol. 57, Issue 7, no. 111
- Publisher Link
- http://dx.doi.org/10.1007/s00348-016-2198-5
- Publisher
- Springer
- Resource Type
- journal article
- Date
- 2016
- Description
- In this paper, we assess the local isotropy of higher-order statistics in the intermediate wake region. We focus on normalized odd moments of the transverse velocity derivatives, [formula could not be replicated] and [formula could not be replicated], which should be zero if local isotropy is satisfied (n is a positive integer). It is found that the relation M2n+1(∂u/∂z)∼R−1λ is supported reasonably well by hot-wire data up to the seventh order (n=3) on the wake centreline, although it is also dependent on the initial conditions. The present relation N3(∂u/∂y)∼R−1λ is obtained more rigorously than that proposed by Lumley (Phys Fluids 10:855–858, 1967) via dimensional arguments. The effect of the mean shear at locations away from the wake centreline on M2n+1(∂u/∂z) and N2n+1(∂u/∂y) is addressed and reveals that, although the non-dimensional shear parameter is much smaller in wakes than in a homogeneous shear flow, it has a significant effect on the evolution of N2n+1(∂u/∂y) in the direction of the mean shear; its effect on M2n+1(∂u/∂z) (in the non-shear direction) is negligible.
- Subject
- isotropy; transverse velocity derivatives; homogeneous shear flow
- Identifier
- http://hdl.handle.net/1959.13/1348652
- Identifier
- uon:30242
- Identifier
- ISSN:0723-4864
- Language
- eng
- Reviewed
- Hits: 1782
- Visitors: 1939
- Downloads: 0
Thumbnail | File | Description | Size | Format |
---|