Axial Segregation in Granular Media

CTS-9501437将对颗粒材料二元混合物中轴向分离和混合的物理机制进行实验研究。部分填充颗粒状材料的水平圆柱体沿其长轴旋转。颗粒尺寸分离和轴向混合是二元混合物及其动态响应角、圆柱体尺寸和转速的函数。发现这一过程是由两种相互竞争的机制决定的，即Fickian扩散和漂移电流。在实验过程中，颗粒材料(玻璃珠)的直径、质量和表面粗糙度将发生系统的变化。可逆偏析效应将作为相变进行研究，微观扩散系数将被确定，并将寻求对颗粒材料和复杂的非牛顿流体系统中一般的轴向偏析过程的基本了解。这项研究将为设计基于颗粒物料混合和分离的工业流程提供指导。***

ABSTRACT CTS-9501437 An experimental study will be undertaken on the physical mechanisms underlying axial segregation and mixing in binary mixtures of granular materials. A horizontal cylinder partly filled with granular material is rotated along its long axis. Particle size segregation and mixing in the axial direction occur as a function of the binary mixture and their dynamic angle of response, cylinder dimensions and rotational speed. The process is found to be determined by two competing mechanisms, the Fickian diffusion and a drift current. The diameter, mass and surface roughness of granular material (glass beads) will be systematically varied during experiments. The reversible segregation effect will be investigated like a phase transition, microscopic diffusion coefficients will be determined, and basic understanding of the generic axial segregation processes in granular materials and complex non-Newtonian fluid systems will be sought. The research will provide guidance to design industrial processes based on mixing and segregation of granular materials. ***