In this paper a standard k-ε model is used to predict the turbulent flow generated by an axial impeller in a cylindrical baffled vessel. The model predictions successfully reproduce the three dimensional characteristics of flow, and are in good agreement with those obtained by PDA measurement.The simulation results show that the ratio of impeller diameter to tank diameter ( D/T )has a great effect on the flow pattern in a stirred tank.For the small diameter impeller,such as D =0 35 T ,t...