A method of correction for the binormal velocity fluctuation using the look-up inversion method for hog-wire anemometry

摘要

This paper concerns the interpretation of the time averaged signals from a crossed hot-wire probe and the development of a related look-up inversion method. By making use of the look-up inversion method, an accurate calibration relationship for the crossed hot-wire probe is obtained. In standard signal analysis methods it is assumed that the mean binormal velocity component W{top}- and its fluctuations w' are both equal to zero. However, in turbulent flows, the fluctuations of the binormal velocity component are not equal to zero. This may lead to large errors in the measured Reynolds stresses. In the present study, a correction method is applied to take the effect of the fluctuating binormal velocity component into account. An assessment of the accuracy of standard signal analysis methods is given. It is demonstrated that the influence of the fluctuating binormal velocity component cannot be neglected if accurate flow measurements are required.