NUMERICAL-ANALYSIS OF POWER-CONSUMPTION AND MIXING TIME FOR A PSEUDOPLASTIC LIQUID IN GEOMETRICALLY SIMILAR STIRRED VESSELS WITH SEVERAL KINDS OF PLATE-TYPE IMPELLERS

A numerical analysis method of estimating power consumption for a pseudoplastic liquid in stirred vessels fitted with various plate impellers is first presented in terms of the energy dissipation distribution in the vessels. The pseudoplastic liquid used was a 1.2 wt.% aqueous solution of hydroxyethyl cellulose. Good agreement between numerically analysed results and experimental data of power consumption in a model vessel of 0.2 m diameter with various impellers and in a vessel of 0.4 m diameter with a paddle impeller proved the method to be sufficiently reliable. Subsequently, the same analysis and mixing analysis were numerically performed for geometrically similar large-scale vessels of 0.4, 0.6 and 0.8 m diameters. It was ascertained from these analyses that the relation between the scale-up ratio and the power consumption, mixing time, and mixing energy can be quantitatively estimated by a numerical analysis of stirred vessels with various types of stirring impellers for a pseudoplastic liquid.