Hydrodynamics and mixing characterization in a novel high shear mixer
Artikel i vetenskaplig tidskrift, 2017
In the present study hydrodynamics and mixing characteristics in a novel batch rotor-stator mixer (RSM), which is very simple in construction and design, is investigated at different rotor speeds (2000, 4000 and 6000 rpm). The proposed RSM design is comprised of tilted jets/holes in the stator, for the deep penetration in the mixing vessel. For the optimization of operating as well as geometrical parameters of the proposed mixer design, simulations are carried out using transient sliding mesh with k-ε turbulence model at different rotor speeds. It was observed that besides radial and tangential flows jets emerging from stator holes impinge the bulk fluid above and below the stator, which improves mixing and reduces dead zones. Further, the flow parameters such as mass flow rate, Power number, Flow number, pumping efficiency and energy dissipation rate increased with an increase in rotor speed. Further, the energy dissipation rate is found maximum in the rotor swept region. It is observed that the amplitude fluctuations in flowrate and torque, with blade position, increased with the rotor speed. Further, mixing characterization in the novel RSM is studied for the first time in a batch RSM to predict the dead zones in the RSM.
High shear mixing
Computational fluid dynamics
k-ε turbulence modeling