Numerical Simulation of the Laminar Flow Field in Stirred Tank with Double layer Combined Impeller Stirring Eccentrically*

摘要

Computational fluid dynamics (CFD) method was applied to study the flow field in cylindrical stirred tank mixing non-Newtonian fluid with double layer combined impeller of upper-straight-blade and lower-inclined-blade. The laminar model and the multiple reference frame (MRF) were employed to simulate the three-dimensional flow field in stirred tank with double layer combined impeller rotating at a constant speed of 200 r/min mixing the mixture of glycerin and water centrally, eccentrically and relative eccentrically, and three different flow structures in stirred tank were obtained. Analyzing the velocity vectors, the velocity contours and the axial, radial and tangent velocity distribution curves, the rule of velocity field with the blade combined form and the stirring structure was discussed. The research provided the valuable reference for the design and practical application of the laminar stirred tank.