Phase-resolved three-dimensional LDA measurements in the impeller region of a turbulently stirred tank

Predictions on the quality of mixing in a turbulently operated stirred tank ask for a detailed knowledge of the flow field, including its turbulence characteristics. In this paper we present the results of three-dimensional, angle-resolved LDA measurements in the vicinity of a Rushton turbine in a baffled tank at Re=29,000. For optimal coincidence of the signals in the three velocity channels, an accurate laser beam alignment procedure was developed. The average flow field is characterized in terms of velocity and vorticity fields. In the characterization of the turbulence, the emphasis is on the anisotropy of the Reynolds stress tensor.