The purpose of this work is to investigate the capability of the currently available CFD tools to correctly forecast the homogenisation process in a baffled vessel stirred with sets of identical Rushton turbines mounted with different spacings. The results of the simulations are compared with experimental data for the validation of the computational procedure. The simulations provide a good prediction of the time evolution of tracer dispersion inside the vessel volume for all the geometrical configurations. The differences in mixing performance due to flow variations occurring as a result of the modification of the impeller number and spacing are correctly forecasted.