Effect of finite spatial resolution of hot-wire anemometry on measurements of turbulence energy dissipation

Abstract

The authors deal with the effect of finite hot-wire resolution which reveals itself when both the one-dimensional energy spectrum in a high wavenumber range and turbulence energy dissipation are measured with a hot sensor of a finite wire length. The proposed correction functions derived for isotropic and homogeneous turbulence structures are based on the assumption that the hot-wire sensitivity to velocity fluctuations follows the local excess of the hot-wire temperature Theta w( xi 2) over the ambient temperature Theta a of the flowing medium. The theoretical predictions compared with experimental data show that the measured quantities may effectively be corrected by means of the correction functions proposed.