Improved suspension quality and liquid level stability in stirred tanks with Rotor-Stator agitator based on CFD simulation

Abstract

The solid-liquid mixing is an important operation unit in the preparation of composites by stirring casting. High quality composite materials need good homogeneity and stable liquid level. In this work, the performances of the Rotor-Stator agitator for solid suspension in stirred tank were investigated through CFD modeling, including the homogeneity, power consumption and liquid level stability. The Eulerian-Eulerian (E-E) multiphase model and the RNG k-ε turbulence model were adopted for modeling the multiphase flow and the turbulence effects, respectively. The effect of various important parameters such as stirring speed, particle size, solid loading and the use of baffles were examined. Adding a stator structure with array holes outside the rotor can optimize the flow pattern, thereby improving the mixing uniformity and liquid level stability. The homogeneity and liquid level stability attained by the Rotor-Stator agitator were better than those for the A200 (an axial-flow agitator) and the Rushton (a radial-flow agitator).