par Burattini, Paolo 
;Lavoie, Philippe;Antonia, Robert
Référence Experiments in fluids, 45, 3, page (523-535)
Publication Publié, 2008-09
;Lavoie, Philippe;Antonia, RobertRéférence Experiments in fluids, 45, 3, page (523-535)
Publication Publié, 2008-09
Article révisé par les pairs
| Résumé : | We investigate the effect of the hot wire resolution on the measurement of the velocity derivative skewness in homogeneous isotropic turbulence. Single- and cross-wire configurations (with different lengths and separations of the wires, and temporal sampling resolution) are considered. Predictions of the attenuation on the basis of a model for the energy spectrum are compared to experimental and numerical data in grid and box turbulence, respectively. It is shown that the model-based correction is accurate for the single wire but not for the cross-wire. In the latter case, the effect of the separation between the wires is opposite to that found in the experiments and simulations. Moreover, the attenuation predicted by the numerical data is in good agreement with that observed in the experiment. For both probe configurations, the sampling resolution has a sizeable attenuation effect, but, for the X-probe, the impact of the separation between the wires is more important. In both cases, the length of the wires has only a minor effect, in the non-dimensional range of wire length investigated. Finally, the present experimental data support the conclusion that the skewness is constant with the Reynolds number, in agreement with Kolmogorov's 41 theory. © 2008 Springer-Verlag. |
