Liquid‐phase mixing in an unbaffled agitated vessel with an unsteady forward–reverse rotating impeller

For an unbaffled agitated vessel with an unsteady forward–reverse rotating impeller, whose rotation reverses its direction with a constant angular displacement, the progress of liquid‐phase mixing was studied experimentally in relation to the characteristics of the liquid flow produced by the impeller. The forward–reverse rotating disk turbine impeller with six flat blades has about 1.5 times the shear level of a unidirectionally rotating impeller of identical design. The turbulence generated in the liquid was more intense within the vessel agitated by the forward–reverse rotating impeller. In the forward–reverse agitation mode, the agitation function of the impeller demonstrably enhanced the liquid‐phase mixing, which shows a pattern with a higher level of mixedness. Copyright © 2007 Curtin University of Technology and John Wiley & Sons, Ltd.