Numerical optimization for blades of Intermig impeller in solid–liquid stirred tank

Abstract

The multiphase flow in the solid–liquid tank stirred with a new structure of Intermig impeller was analyzed by computational fluid dynamics (CFD). The Eulerian multiphase model and standard k–ε turbulence model were adopted to simulate the fluid flow, turbulent kinetic energy distribution, mixing performance and power consumption in a stirred tank. The simulation results were also verified by the water model experiments, and good agreement was achieved. The solid–liquid mixing performances of Intermig impeller with different blade structures were compared in detail. The results show that the improved Intermig impeller not only enhances the solid mixing and suspension, but also saves more than 20% power compared with the standard one. The inner blades have relatively little influence on power and the best angle of inner blades is 45°, while the outer blades affect greatly the power consumption and the optimized value is 45°.