Power Consumption of an Impeller System

This close-clearance impeller has a diameter ratio of 0.9-0.98. Its main duty consists essentially of minimizing the highly viscous boundary layer clinging to the vessel wall, thus improving the heat transfer. 

The generation of a three-dimensional flow pattern inside a vessel together with the corresponding energy dissipation and shear stress of course is linked to a certain 

Generally, the resisting power is made up of inertial forces and internal friction. As the relative velocity due to the complex flow pattern cannot be exactly derived, the proportional tip speed 

Together with this, for the resulting power the following relationship is valid  

To calculate the impeller power or shaft power brought into the system, the following equation is widely used  

---