Numerical Simulation of Flow Field in a Stirred Reactor

The flow field feature in a stirred reactor has been studied by numerical simulation.This study uses k-e Two-Equation turbulent model,and disposes the area around stirring impeller with multi-reference frame method.As the results show,the flow field generated by the improved arc blade impeller has typical radial flow feature,and the axial flow has been enhanced.The turbulent model of Standard k-e and RNG k-e both can accurately predict axial maximum velocity in stirred tank,and the outcome of RNG k-e model is more accurate.The turbulent energy in stirred tank is mainly generated in the area around impeller and near tank wall.But the area under stirring impeller is influenced by circular flow more weakly,and the parameter k is smaller.So the stirring impeller should be located more near towards the bottom of stirred tank,or should use folding blade impeller with 45 degree pitch angle,in order to enhance the axial delivering capability of stirring impeller and improve the mixing effect.