Characterisation of the turbulence in a stirred tank using particle image velocimetry

In this study, angle-averaged flow fields of the liquid in the vicinity of a Rushton impeller in a stirred tank were measured with the use of Particle Image Velocimetry (PIV). Global parameters such as flow number are calculated from local mean velocities and compared with literature values obtained with LDA. Macro lengths scales and the dissipation rate of kinetic energy fields have been calculated. The anisotropy of the turbulence in the impeller stream has been characterised and quantified. Finally, the development of the eddies generated by the turbine has been observed and their trajectory outside the blades has been determined.