Investigations of the NS-alpha model using a lid-driven cavity flow
| dc.creator | Scott, K. A. | |
| dc.creator | Lien, F. S. | |
| dc.date | 2007-11-02 | |
| dc.date | 2008-05-22 | |
| dc.date.accessioned | 2026-07-07T09:40:03Z | |
| dc.date.available | 2026-07-07T09:40:03Z | |
| dc.description | In this paper we investigate a subgrid model based on an anisotropic version of the NS-$α$ model using a lid-driven cavity flow at a Reynolds number of 10,000. Previously the NS-$α$ model has only been used numerically in the isotropic form. The subgrid model is developed from the Eulerian-averaged anisotropic equations [Holm, \textit{Physica D}, v.133, pp 215-269, 1999]. It was found that when $α^{2}$ was based on the mesh numerical oscillations developed which manifested themselves in the appearance of streamwise vortices and a `mixing out' of the velocity profile. This is analogous to the Craik-Leibovich mechanism, with the difference being that the oscillations here are not physical but numerical. The problem could be traced back to the discontinuity in $α^{2}$ encountered when $α^{2}=0$ on the endwalls. An alternative definition of $α^{2}$ based on velocity gradients, rather than mesh spacing, is proposed and tested. Using this definition the results with the model shown a significant improvement. The splitting of the downstream wall jet, rms and shear stress profiles are correctly captured a coarse mesh. The model is shown to predict both positive and negative energy transfer in the jet impingement region, in qualitative agreement with DNS results. | |
| dc.description | 22 pages, 11 figures; changes to Section 2 and Section 4.2 | |
| dc.identifier | https://arxiv.org/abs/0711.0354 | |
| dc.identifier | http://arxiv.org/abs/0711.0354 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/161367 | |
| dc.subject | Fluid Dynamics | |
| dc.title | Investigations of the NS-alpha model using a lid-driven cavity flow | |
| dc.type | text |