In this investigation, the ability of the URANS turbulent models to predict the instantaneous flow is tested by means of different assumptions. In fact, CFD simulations of the hydrodynamic behavior induced by a Rushton turbine (RT) in a fully baffled vessel operating in a turbulent regime have been presented. Numerical results obtained with symmetrical and asymmetrical zones of the stirred tank and different turbulence models have been compared with the PIV experimental data. Results shows that the k − ε turbulence model applied in the entire tank is able to predict the macro-instabilities inside the vessel.