Agreement of experimental liquid velocity distributions in the tank and theoretical values calculated on the basis of a model of liquid flow in the tank with a pitched-blade impeller in a laminar motion [8] was investigated. Peripheral and axial velocity distributions in the tank with 6 impellers of different geometrical parameters and various operating parameters were compared. Good agreement of compared values was obtained. On the basis of the model the pumping efficiency of impellers was calculated and compared with literature data.