V.A.Voskoboinick Cross-correlations and spectra of the turbulent pressure fluctuations on the streamlined dimple surface |
Acoustic bulletin, Vol. 14 ¹ 2, (2011) |
| The paper deals with presenting of the results of experimental studying of wall-pressure fluctuation field forming at the turbulent flowing above the deep spherical dimple. The behavior of the cross-correlation and spectral characteristics shows that the inclined asymmetric large-scale vortices are generated inside the dimple. These vortex structures are switched from one tilt to another, exciting the low-frequency modulating oscillations. The inclined location of the vortex structures stipulates the appearance of anticorrelation (the antiphase oscillations) in wall-pressure fluctuation field at the opposite lateral walls of the spherical dimple. In course of evolution, the asymmetric vortices are ejected above the aft wall of the dimple and their ejection angle increases with the Reynolds number. |
|
KEY WORDS: streamlining of dimples, vortex structures, pressure fluctuations, pseudosound, power spectral density, correlation characteristics |
| TEXT LANGUAGE: Russian |