为掌握磨煤机分离器中气固两相流运动行为与煤粉分离过程，针对实验室规模磨煤机分离器中气固两相流行为开展数值模拟。在欧拉−拉格朗日方法的框架下，采用Realizable k-ɛ湍流模型描述气相场，采用附加随机轨道模型的离散相模型描述煤粉颗粒运动，在网格无关性验证的基础上，将单向耦合和双向耦合模拟结果与实验进行对比，发现双向耦合方法得到的煤粉颗粒粒径分布与实验数据的吻合更好。进一步采用双向耦合方法，对实验室规模磨煤机分离器中气相流动行为、颗粒运动特性和分离器性能进行研究。结果表明，采用双向耦合模拟时，颗粒溢出更晚且所经历的时间更长。受颗粒影响，筒体内壁与内锥体外壁附近气流速度差异增大，内锥体内气流速度分布均匀性变差，一次分离区与二次分离区出现明显的回流区。随着进口气流速度的增加，颗粒溢出率升高，颗粒排放率线性下降；进口气流速度对总颗粒返料率影响较小，但对分级返料率有重要影响。进口气流速度较低时，分级返料率呈单峰分布，气流速度较高时，分级返料率呈双峰分布。进口气流速度一定时，随着颗粒直径增大，分级分离效率增加；进口气流速度越大，分级分离效率随颗粒直径增加得越缓慢，分离器的切割粒径越大。

In order to understand the behavior of gas-solid two-phase flow motion and the process of pulverized coal separation in coal mill separator, the numerical simulations on the gas-solid two-phase flow in the separator of a laboratory-scale coal mill were carried out. In the framework of the Eulerian-Lagrangian method, the realizable k-ɛ turbulence model was used to describe the gas-phase field and the discrete phase model with the random walk model was used to describe the pulverized coal particle motion in the simulations. On the basis of cell independence verification, the results of one-way coupling and two-way coupling simulations were compared with the experiments. It is found that the particle size distribution of pulverized coal obtained by the two-way coupling method agrees better with the experimental data than that obtained by the one-way coupling method. The gas phase flow behavior, particle motion characteristics and separator performance in the laboratory-scale coal mill separator were further investigated using a two-way coupling method. The results show that the particle overflow occurs later and the overflow lasts longer when using the two-way coupling method. Because of the effect of particles, the airflow velocity difference between the inner wall of the separator and the outer wall of the inner cone of the separator becomes large, and the uniformity of airflow velocity distribution in the inner cone becomes poor, and there are obvious backflow regions in the primary and secondary separation zones. With the increase of the inlet airflow velocity, the particle overflow rate increases, and the particle discharge rate decreases linearly. The inlet airflow velocity has a small influence on the total particle return rate but has a profound influence on the grade return rate. The grade return rate exhibits a unimodal distribution at the lower airflow velocity, and it displays a bimodal distribution at the higher airflow velocity. When the inlet airflow velocity remains constant, the grade separation efficiency increases as the particle diameter increases. The greater the inlet airflow velocity, the slower the grade separation efficiency increases with the particle diameter, and the larger the cut-off diameter of the separator.