Multi-objective Geometrical Optimization of Single and Dual Impeller Stirred Tanks: an Application of the Mean Age Theory Approach

Multi-objective optimizations are performed for single and dual-impeller systems. The steady-state mean age theory approach with a novel method developed in previous work is applied for mixing time prediction. The three-blade Pitched-blade turbines are the baseline designs. The study aims to find the optimum impellers with lower mixing time and power consumption than the benchmark designs. The blade consists of two parts characterized by 10 to 12 design parameters, and 120 designs are investigated during optimization. The parameter analysis study highlights that the angle formed by the line connecting the two parts is the most critical parameter affecting mixing performance and power input in both systems. Compared to the baseline design, experimental results show that the optimum designs from single and dual impeller optimization reduce the power consumption 10% and 35%, respectively. However, the reduction in mixing time is not significant. Designs that have lower power numbers with higher power input reduce mixing times by 20%–30%.