Investigation of the free turbulent swirl jet behind the axial fan

Abstract

Experimental investigation of the free turbulent swirl jet behind the axial fan, by use of the three-component laser Doppler anemometry is presented in this paper. Axial fan generates Rankine swirl. Measurements have been performed in five vertical measuring sections downstream for one rotation number 1500 rpm. Time averaged velocity components and their profile transformation downstream were investigated. Statistical moments of the second, third and fourth order have been calculated and presented. The highest turbulence levels are reached in the central zone, more precisely - shear layer zone and in the injection zone. Skewness and flatness factors differ from normal Gaussian distributions. Turbulence swirl flow anisotropy is investigated by applying invariant maps. Most of the obtained results are positioned in the region of the three-component isotropic turbulence and axisymmetric expansion.