Abstract Studies on powder mixing in industrial mixers are crucial for the improved criteria of mixing equipment design and optimization within various mixing unit operations. In the present study, a series of simulation for the powder mixing in an elaborately designed mixer, called a cross-torus paddle mixer, is conducted using the Advanced DEM-CFD method. The effects of various operational parameters on the mixing performance are analyzed and discussed in detail. Through these investigations, it is found that rotational speed, filling level, liquid viscosity, and paddle obliquity can significantly affect mixing performance. Owing to a much-enhanced convective motion of particles, a higher rotational speed exhibits a more efficient mixing process. Smaller number of particles inside the vessel shows the better mixing performance, which is attributed to an enhanced diffusive motion of particles. Decreasing the liquid viscosity or increasing the paddle obliquity can also result in a more efficient mixing in a diffusive dominant mode. By performing the simulation of mixing behavior in a mono-dispersed system, the present work provides significant evidence and novel insights to further understand the mixing mechanisms.

中文翻译：

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基于DEM-CFD方法的交叉圆环桨叶混合器混合机理的数值研究

摘要 工业混合机中粉体混合的研究对于改进各种混合单元操作中混合设备设计和优化的标准至关重要。在本研究中，使用高级 DEM-CFD 方法对精心设计的混合器（称为交叉环桨式混合器）中的粉末混合进行了一系列模拟。详细分析和讨论了各种操作参数对混合性能的影响。通过这些调查发现，转速、填充水平、液体粘度和桨叶倾角会显着影响混合性能。由于粒子的对流运动大大增强，更高的旋转速度表现出更有效的混合过程。容器内颗粒数越少，混合性能越好，这归因于粒子的增强扩散运动。降低液体粘度或增加桨叶倾角也可以导致在扩散主导模式下更有效的混合。通过对单分散系统中的混合行为进行模拟，本工作为进一步了解混合机制提供了重要的证据和新颖的见解。