A modeling and simulation method of free-surface flow fields in unbaffled stirred tanks was established based on the volume of fluid (VOF) multiphase model.The validity of this method was tested by studying the turbulent flow fields in the eccentric and unbaffled concentric stirred tank agitated by a Rushton impeller.The detached eddy simulation (DES) and the standardk-εturbulence model were employed to simulate the mean fluid velocities,respectively.Good agreements were found between the numerical and experimental results,only with somewhat under-predictions.The difference between the DES and experimental data is less than 12%,while it is worse for thek-εmodel.Results showed that the combination of the DES and VOF model,as well as the simulation method proposed here,can predict the free-surface hydrodynamics in stirred tanks with satisfactory accuracy.
