CFD STUDY OF MACRO-MIXING IN STIRRED TANKS

摘要

This paper reports on the CFD study of macro-mixing process of Rushton turbine in stirred tank. The code for mixing calculation is developed in the commercial CFD code CFX4.3. Mixing process simulation on different calculation method, different turbulent model and different tracer adding and detecting position are calculated. The simulation is three-dimensional and the impeller region is explicitly included using a sliding mesh method to account for the relative movement between impeller and baffles. Fluid flow is calculated with a turbulent κ-ε and RNG κ-ε model using a finite-volume method. The results show that the mixing time highly relies on the flow field, the feeding and detecting position. The improvements of macro-mixing simulation can be obtained by accurate flow prediction and modification to turbulence models applied to stirred tank.