Power Consumption of Impeller in Agitated Vessel of Continuous Flow System

Abstract

Power consumption of three kinds of six-blade paddle was measured in a continuous-flow agitated vessel in the range of Reynolds number from 10³ to 2×10⁵. The fluid flows in and out through pipes attached to the center of the bottom and to the side wall.
In the case where the fluid was fed into the vessel through the bottom pipe and taken out from the pipe in the side wall, the power number increased with feed rate. In the case of the opposite feed direction, it decreased in a range of low feed rate and then began to increase.
Power consumption was correlated with feed rate and other operation variables based on the balance of angular momentum, and it was found that the difference between the power numbers for continuous system and batch system, ΔN_p, could be expressed as a function of a dimensionless feed rate N_Qf (≡Q_f/nd³).