par Burattini, Paolo 
;Antonia, Robert
Référence Experiments in fluids, 38, 1, page (80-89)
Publication Publié, 2005-01
;Antonia, RobertRéférence Experiments in fluids, 38, 1, page (80-89)
Publication Publié, 2005-01
Article révisé par les pairs
| Résumé : | The effective-angle and look-up-table calibrations are used to reduce X-wire datasets in two flows: decaying grid turbulence at R λ ≃50 and the far field of a circular jet at R λ ≃400 with a mean streamwise velocity of nearly 6ms-1 in each case. A static check, which involves mean values of the velocity components, indicates that the effective-angle calibration incorrectly reduces the range of the estimated velocity components and is therefore likely to be less reliable than the look-up-table approach. The two methods produce significantly different results for both small- and large-scale statistics of the streamwise and, more especially, transverse velocity fluctuations. For grid turbulence, the mean-squared temporal derivatives of the streamwise and transverse velocities are larger by 3% and 19%, respectively, when estimated with the look-up-table method compared to the effective-angle calibration. The increase in the mean-squared transverse velocity derivative yields results in closer agreement with isotropy. At velocities below 6ms-1, the effective-angle is a quantity that strongly depends on the velocity magnitude and direction. © Springer-Verlag 2004. |
