Numerical Simulation of Mixing Process in Stirred Tanks with Dual Rushton Turbines

The mixing process in a stirred tank of 0.476 m diameter with dual six-blade Rushton turbine(DT-6) was numerically simulated using computational fluid dynamics(CFD) package FLUENT(6.0).The RNG κ-e turbulent model and multi-reference frame were used in the simulation.By changing the meshing technology,increasing the number of mesh and decreasing the residual discrepancy,the(effects) of tracer feeding and detecting positions on mixing time were investigated.The momentum and mass equations were computed separately.The shaft power predicted by CFD is in a good agreement with experimental results. Although the mixing time predicted by CFD is better than that reported in literatures,it is still about two times higher than that obtained by experiment.