Survey of multi-wire probe data processing techniques and efficient processing of four-wire probe velocity measurements in turbulent flows

A general presentation of the two main approaches for the extraction of velocity information from multi-wire hot-wire probe measurements is first given, along with a short introduction to the different data processing techniques currently available. This global survey is intended to help researchers interested in using multiwire probes (for velocity measurements) choose more easily a data processing technique adapted to their experiments and laboratory facilities. In the second part, a numerically efficient four-wire probe data processing; technique, especially suited for flows with relatively high turbulence intensities (up to 30%), is described. With this technique, an accurate solution can be found in almost all of the probe's acceptance domain and the directional sensitivity calibration does not have to be performed in situ. The accuracy of the method is demonstrated with a 3D airfoil near-wake experiment for which four-wire probe measurements of mean velocity, full Reynolds stress tensor and triple correlations are compared with three-component LDA measurements.