Abstract: Accounting for the phenomenon of mixed dead zone in mixing process of binary granular systems,column internals wee set in the horizontal drum to augment mixing. The contact number was taken as a particle mixing indicator. The discrete element method was employed to study mixing of the binary particles with the column internals. The mechanisms of augmenting mixing of the column internals were discussed in this paper. The results showed that the column internals can destroy the mixed dead zone of the aggregated particles. When the components are set in the drum,the mechanisms of convection and diffusion are enhanced,and the segregation of the binary particles is suppressed. Moreover,the column internals can improve the mixing efficiency and change the stability of mixing. It was noted that the mixing effect of binary particles improves with the increase of the number of cylinder components in the drum in a certain range,and excessive number of internals are unfavorable for mixing. The column internals inhibit mixing of particle system when the drum starts to rotate,and the internals achieve the purpose of augment mixing after a period of movement. The results can provide theoretical guidance for equipment improvement of particle material in the industry of the augmenting mixing.

Key words: binary granular systems, discrete element method, column internal, mixed dead zone, augmenting mixing

摘要： 针对滚筒内二元颗粒体系在混合过程中产生的混合死区现象，提出在混合死区位置设置柱体内构件的增混方式，以接触数作为混合评价指标，采用离散单元法研究柱体内构件对二元颗粒体系运动混合的影响，并分析其增混机理。研究结果表明：柱体内构件很大程度上破坏了聚集小颗粒的混合死区，强化了二元颗粒间的对流和扩散机制，同时抑制了颗粒的离析作用，提高了颗粒体系整体混合程度，同时，柱体内构件提高了二元颗粒体系的混合效率，改变了颗粒体系混合的稳定性；在一定的范围内，柱体内构件的数量越多，颗粒体系的混合效果越好，但如果数量过多，反而不利于二元颗粒间的混合；在滚筒开始转动的短暂时间内，柱体内构件反而抑制颗粒体系的混合，滚筒继续转动，才起到增混的效果。本研究可为二元颗粒物料增混设备的改进提供参考和依据。

关键词: 二元颗粒, 离散单元法, 柱体内构件, 混合死区, 增混