A method of correction for the binormal velocity fluctuation using thelook-up inversion method for hot-wire anemometry

Abstract

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