CFD simulation of solid–liquid stirred tanks for low to dense solid loading systems

Abstract

Numerous industrial processes require stirred tanks as mixing systems for solids suspension in liquids. Hydrodynamics of such systems is critical for their design and control to improve performance. In particular, modelling multiphase stirred tanks at high solid concentrations is complex due to significant particle-particle and particle-wall interactions, which are generally neglected at low concentrations. Most models do not consider such interactions and deviate significantly from experimental data. Critical factors such as modelling approach, drag, turbulent dispersion, coefficient of restitution and turbulence are examined and discussed exhaustively. A review comparing drag model predictions and their applicability over the range of Reynolds numbers observed in stirred tanks is presented. The Euler–Euler approach with kinetic theory of granular flow provides realistic predictions as it takes the interactions of particles with particles and walls into account. The Syamlal–O’Brien model is found to be the most efficient drag model in the overall prediction of solid suspension. The Reynolds stress model is shown to be a computationally viable alternative to the widely used k-ε model for accurate prediction of turbulence in this turbulence-dominated system.

@article{wadnerkar2016p,
  title         = {CFD simulation of solid--liquid stirred tanks for low to dense solid loading
                  systems},
  author        = {Wadnerkar, Divyamaan and Tade, Moses O. and Pareek, Vishnu K. and Utikar,
                  Ranjeet P.},
  year          = 2016,
  journal       = {Particuology},
  publisher     = {Elsevier},
  volume        = 29,
  pages         = {16--33},
  doi           = {10.1016/j.partic.2016.01.012},
  url           = {https://www.sciencedirect.com/science/article/pii/S1674200116300256}
}