Abstract:

The flow field of spiral ribbon-screw impeller for high viscosity non-Newtonian fluid was studied by computational fluid dynamics simulation. With application examples，the distributions of macro velocity field，shear rate and apparent viscosity were investigated，the effect of rheological index on stirring performance was discussed，and the stirring power was calculated. The results showed that the spiral ribbon-screw mixer had good overall stirring performance. Metzner constant k_s for this type of impeller was equal to 13.8 under simulation conditions，and rheological index had little effect on k_s. This work provided useful guidance and reference for design and application of spiral ribbon-screw impeller for high-viscosity non-Newtonian fluid.

摘要：

应用计算流体力学数值模拟方法，研究了螺带-螺杆组合式搅拌器对高黏度非牛顿流体的搅拌流场特性。结合实例，考察了宏观流场、速度场、剪切速率和表观黏度的分布，分析了流变指数对搅拌特性的影响，并计算了不同工况下的搅拌功率。结果表明：螺带-螺杆组合搅拌器针对高黏度流体，具有良好的全局搅拌特性，在本文的模拟条件下，组合桨的Metzner常数k_s约为13.8，而流变指数变化对k_s的影响不大，为螺带-螺杆搅拌桨在高黏度非牛顿流体搅拌中的应用提供有益指导和参考。