An Investigation into Different Power Consumption Parameters of Rushton Turbines: A Computational Survey

Abstract

SummaryIn the present work, the mixing process of shear thinning liquids in a six-blade Rushton turbine is studied. A finite volume based computational fluid dynamics (CFD) simulation has been carried out and the three-dimensional turbulent flow is numerically analyzed by using the Shear Stress Transport k-ω (k-ω SST) model. Shear thinning liquids were investigated and shear thinning behaviour was modelled by the Ostwald-de Waele law. The used stirred vessel has a cylindrical shape with a flat bottom and the liquid height was kept equal to the vessel diameter. Effects of the power law index and the angle of attack of the blade on power consumption have been investigated. The results show that decreasing the angle of attack from 90° to 45° not only results in an increase in the flow rate down to the bottom of the vessel, resulting in a better mixture qualification, but also reduces the power consumption of the stirring process. To verify the simulation, axial, radial and tangential velocity components were compared with other experimental data and satisfactory agreement was found.

Investigation of the Performance of V-cut Turbines for Stirring Shear-thinning Fluids in a Cylindrical Vessel

“…The energy consumption is another important parameter to be considered in stirred tanks. For Rushton turbines, the power input may be reduced by decreasing the blade attack angle from 90° to 45° [6]. Beloudane et al [7] designed a converging hollow blade to enhance the hydrodynamic characteristics and reduce the power consumption of radial impellers.…”