The hydrodynamic characteristics generated by the standard Rushton or 45°-upward pitched-blade-turbine (PBT) impellers in a baffled reactor are numerically simulated for different off-bottom clearances (C = 1/3Hand 1/2H) and agitator speeds (100, 150, 200, 250 and 300r.min-1) by using FLUENT code (Version 5.4). Theresults are compared with the experimental and simulated data in the published papers and good agreement isobserved. The shapes of the profile of mean velocities seem independent to the speed of agitators under theexperimental conditions (100-300 r.min-1).