Enhanced dispersive mixing can be achieved by harnessing extension‐dominated flows, because they are more efficient in agglomerate/droplet breakup than shear‐dominated flows. Herein, we compare computationally the performance of two single‐screw extrusion mixing sections with significant extensional flow components, the Chris Rauwendaal dispersive (CRD) mixer and the extensional mixing element (EME), recently proposed by the authors. Tapered slots in the CRD and hyperbolic contractions in the EME attempt to create extensional stresses through significant velocity gradients. Our studies confirm that EMEs are a better dispersive mixer than the CRD mixer, as they impose more intense and uniformly distributed extensional flow in a higher volume fraction of the material, and with less specific mechanical energy consumption. Overall, the EME design with a biaxial contraction was found to be the best dispersive mixer for single‐screw extruders (SSE). The manuscript also summarizes all the existing dispersive mixers for SSE and ranks them relatively for their dispersive mixing capability.

中文翻译：

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用于单螺杆挤出机的拉伸支配混合器中分散混合的比较计算分析

通过利用扩展支配的流可以实现增强的分散混合，因为它们在团聚体/液滴破碎方面比剪切支配的流更有效。本文中，我们在计算上比较了作者最近提出的两个具有显着拉伸流分量的单螺杆挤出混合段的性能，即Chris Rauwendaal分散（CRD）混合器和拉伸混合元件（EME）。CRD中的锥形槽和EME中的双曲线收缩试图通过明显的速度梯度产生拉伸应力。我们的研究证实，与CRD混合器相比，EME是一种更好的分散混合器，因为它们在较高的材料体积分数中施加了更强烈且均匀分布的拉伸流，并且具有较低的比机械能消耗。总体，发现双轴收缩的EME设计是用于单螺杆挤出机（SSE）的最佳分散混合器。该手稿还总结了所有现有的SSE分散混合器，并对其分散混合能力进行了相对排名。