Analysis of mixing efficiency of rushton turbines based on CFD models

Abstract

The required power and the flow pattern in a vessel mostly depend on the impeller geometry. In the literature, there are only recommendation and no indices to help choosing the proper impeller for a defined mixing task. And it is not possible to determine the optimal rotating speed for impellers applied in different mixing tasks. The primary goal of our research is to compare the quantitative characterization of the level of homogeneity in a stirred system obtained by using different impeller geometries and rotating speed. Therefore, the developed flow patterns are characterized by logarithmic histogram of the distribution of velocity field. To validate the proposed characterization technique the mixing time resulted by the different geometries are also calculated. The comparison of the mixing efficiency based on the determined power number. All these models require some measurements to be validated. Hence, a laboratory experimental system was built to measure the power consumptions of the investigated impellers.