CFD simulation of chemical engineering processes in stirred tank reactors

Term: from 05 / 2004

Funding: base funding




Mixing in stirred vessels is a common operation in the process industry, especially in the fine chemistry, the pharmaceutical industry and the biotechnology. In these branches, STR are widely used for batch and semi-batch processes. Numerical modelling and simulation of mixing processes in STR can contribute to:

  • simplification of scale-up procedures in the stage of process development,

  • process and plant optimisation,

  • hazard analyses and evaluation.


CFD (Computational Fluid Dynamics) methods are applied to numerical flow simulation in stirred tank reactors, where CFX® is used as simulation software.

The simulation results are validated experimentally using the following imaging techniques:

  • videometry,

  • X-ray tomography (e.g. cone beam tomography),

  • Gamma tomography.


Transient mixing of initially stratified different density liquids in a stirred tank reactor after stirrer start-up

Vergl_Exp_CFD-Simulation_engl Konz_kurve_CFD_engl

Gassing of a liquid in a stirred tank reactor using a gas inducing turbine stirrer



Gas hold-up in the impeller region

Further information

A study on the mixing behaviour of different densities liquids in a stirred tank by passive and reactive tracers (Poster)

Measurement and CFD prediction of a two-phase flow in a STR  (Presentation)




  • H.V. Hristov, S. Boden, U. Hampel, H. Kryk; Numerical Simulation of a Two-Phase Flow in a Stirred Reactor; Proceedings of 6th International Conference on Multiphase Flow, paper PS6_8, 978-3-86010-913-7
  • H.V. Hristov, H.-M. Prasser, H. Kryk, G. Hessel, W. Schmitt; Mixing behaviour of different density liquids in a stirred tank reactor; Chem. Eng. Res. Des. (submitted)


Dr. H.V. Hristov, Dr. H. Kryk