Abstract: Heavy medium cyclones have been widely used in the field of coal preparation. The fine particles of Si and SiC in different densities are likely aggregated，resulting in difficulties in chemical separation. This paper presented an experiment in the separation of Si particles from SiC particle using a heavy medium mini-cyclone. Simulation of the tangential velocity in the heavy-media mini-cyclone was conducted in order to study the flow field characteristics，and the influences of density and viscosity on the tangential velocity in the cyclone. The simulation software was CFD Fluent. Results showed that the influences of the viscosity were greater than the density. The tangential velocity increased when the density of the heavy medium increased. The tangential velocity decreased with the increase in the viscosity of the heavy medium. The swirling decayed more quickly in smaller cyclones.

Key words: mini-cyclone, heavy-medium, density, viscosity, tangential velocity

摘要： 重介质旋流器在选煤领域中已得到广泛应用。根据硅和碳化硅等不同密度微细颗粒易团聚且难用化学方法分离的特点，本文选用重介质微型旋流器对其进行分离。为探索重介质微型旋流器的流场特性，本文基于CFD软件Fluent对重介质微型旋流器的切向速度场进行了数值模拟研究，考察了介质的密度及黏度对旋流器内切向速度的影响。结果显示，密度不变，黏度增大，切向速度减小，且旋流器直径越小，切向速度减小越快，即旋流强度衰减得越快。虽然黏度不变时密度的增大会导致切向速度的增加，但当密度和黏度按实际重介质溶液同时增大时，黏度对切向速度的影响远大于密度的影响。

关键词: 微型旋流器, 重介质, 密度, 黏度, 切向速度