Numerical Investigation of the Performance of Kenics Static Mixers for the Agitation of Shear Thinning Fluids

Authors

1 Polytechnic National School of Oran (ENPO), 31000, Algeria

2 Department of Technology, Institute of Science and Technology, Ahmed Salhi University Center of Naâma (Ctr Univ Naâma), PB 66, 45000, Algeria

Abstract

The laminar flow of non-Newtonian fluids through a Kenics static mixer is investigated by using the CFD (Computational Fluid Dynamics) tool. The working fluids have a shear thinning behavior modeled by the Ostwald De Waele law. We focus on the effect of Reynolds number, fluid properties, twist angle and blade pitch on the flow characteristics and energy cost. The pressure drop information obtained from the simulations was compared to several experimental correlations and data available in the literature. The numerical results were found in good agreement with the experimental values. From the obtained results, the twist technique is confirmed to be very useful to enhance the mixing with less power consumption and at low Reynolds numbers. A faster axial mixing has been achieved with increased blade length and decreased twist angle. However, the good mixing near the tube walls was obtained with increased twist angle. The power consumption expressed in power drop was found to be increase with increased CMC concentrations, Reynolds number, twist angle and decreased blade length.

Keywords