Mixing and Flow Visualization in Agitated Vessels of Different Geometries

Mamdouh M. Nassar^a,*, A. M. El-kersh^b, Ebrahiem E. Ebrahiem^a, Mohamed S. Mahmoud^a.

^aDepartment of Chemical Engineering Minia University, El-Minia, Egypt

^bDepartment of Mechanical Power & Energy Engineering Minia University, El-Minia, Egypt

^*Corresponding author. Tel.: +20862362083, E-mail address: Mamdouh_Nassar@yahoo.com

Abstract

An experimental investigation of the mixing in agitated vessels of different geometries is carried out. Vessels with different geometries, [circular baffled, circular unbaffled, rectangular, triangular, hexagonal, and octagonal] are used. The effect of power consumption, and dimensionless mixing time have been considered. The Flow visualization of the tested vessels showed that eddies formed by vessels with sharp angles [triangle shape] is higher than that formed by baffled vessels. Measurement of Power number as function of Reynolds number for the tested vessels indicated that vessel geometry has an effect on power consumption for mixing and each increase in number of side walls causes a decrease in power consumption till reach circular unbaffled vessel. In addition, the impeller shape has an effect on power consumption for the same vessel. Measurement of energy per unit volume for the tested vessels indicated that energy per unit volume for triangular and circular baffled vessels is always higher than other vessels in the whole range of N_Re tested.