CFD prediction of mean flow field and impeller capacity for pitched blade turbine

Abstract

This work focused on exploring a computational fluid dynamics(CFD)method to predict the macro-mixing characteristics including the mean flow field and impeller capacity for a 45° down-pumping pitched blade turbine( PBT)in stirred tanks. Firstly, the three typical mean flow fields were investigated by virtue of three components of liquid velocity. Then the effects of impeller diameter(D)and off-bottom clearance(C)on both the mean flow field and three global macro-mixing parameters concerning impeller capacity were studied in detail. The changes of flow patterns with increasing C/D were predicted from these effects. The simulation results are consistent with the experimental results in published literature.

Keywords

CFD simulation / PBT / stirred tank / flow field / pumping capacity

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