Khujadze, George and Nguyen van yen, Romain and Schneider, Kai and Oberlack, Martin and Farge, Marie (2011):
Coherent vorticity extraction in turbulent boundary layers using orthogonal wavelets.
318, In: Journal of Physics: Conference Series, (2), Institute of Physics, pp. 022011/1-022011/10, ISSN 1742-6588, [Online-Edition: http://stacks.iop.org/1742-6596/318/i=2/a=022011],
[Article]
Abstract
Turbulent boundary layer data computed by direct numerical simulation are analyzed using orthogonal anisotropic wavelets. The flow fields, originally given on a Chebychev grid, are first interpolated on a locally refined dyadic grid. Then, they are decomposed using a wavelet basis, which accounts for the anisotropy of the flow by using different scales in the wall-normal direction and in the planes parallel to the wall. Thus the vorticity field is decomposed into coherent and incoherent contributions using thresholding of the wavelet coefficients. It is shown that less than 1 of the coefficients retain the coherent structures of the flow, while the majority of the coefficients corresponds to a structureless, i.e., noise-like background flow. Scale-and direction-dependent statistics in wavelet space quantify the flow properties at different wall distances.
| Item Type: | Article |
|---|---|
| Erschienen: | 2011 |
| Creators: | Khujadze, George and Nguyen van yen, Romain and Schneider, Kai and Oberlack, Martin and Farge, Marie |
| Title: | Coherent vorticity extraction in turbulent boundary layers using orthogonal wavelets |
| Language: | English |
| Abstract: | Turbulent boundary layer data computed by direct numerical simulation are analyzed using orthogonal anisotropic wavelets. The flow fields, originally given on a Chebychev grid, are first interpolated on a locally refined dyadic grid. Then, they are decomposed using a wavelet basis, which accounts for the anisotropy of the flow by using different scales in the wall-normal direction and in the planes parallel to the wall. Thus the vorticity field is decomposed into coherent and incoherent contributions using thresholding of the wavelet coefficients. It is shown that less than 1 of the coefficients retain the coherent structures of the flow, while the majority of the coefficients corresponds to a structureless, i.e., noise-like background flow. Scale-and direction-dependent statistics in wavelet space quantify the flow properties at different wall distances. |
| Journal or Publication Title: | Journal of Physics: Conference Series |
| Volume: | 318 |
| Number: | 2 |
| Publisher: | Institute of Physics |
| Divisions: | 16 Department of Mechanical Engineering 16 Department of Mechanical Engineering > Fluid Dynamics (fdy) |
| Date Deposited: | 06 Jan 2012 07:29 |
| Official URL: | http://stacks.iop.org/1742-6596/318/i=2/a=022011 |
| Additional Information: | 13th European Turbulence Conference (ETC13), Warsaw, Poland, 5th - 8th September, 2011 |
| Identification Number: | doi:10.1088/1742-6596/318/2/022011 |
| Export: | |
| Suche nach Titel in: | TUfind oder in Google |
 |
Send an inquiry |
Options (only for editors)
 |
View Item |
Drucken
Impressum