Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.13/41381
- Velocity derivative skewness in isotropic turbulence and its measurement with hot wires
Antonia, Robert A.
- The University of Newcastle. Faculty of Engineering & Built Environment, School of Engineering
- 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.
- Experiments in Fluids Vol. 45, Issue 3, p. 523-535
- Publisher Link
hot wire resolution;
velocity derivative skewness;
homogeneous isotropic turbulence;
- Resource Type
- journal article