采用离散元法对ABS塑料球在筒仓内的流动进行数值模拟，并测定了ABS球的回弹及休止角等微观物性参数，验证了离散元模型中颗粒接触参数的正确性. 基于正交实验法考察了锥形改流体参数对料流的影响，分析了仓壁压力分布规律. 结果表明，锥形改流体参数对物料流型的影响顺序为锥形改流体倾角>锥形改流体距卸料口的高度>锥形改流体高度；锥形改流体倾角<120o时中心流无法转变为整体流. 添加合适的改流体后仓壁所受最大压力减小为原来的一半，最大压力位置上移.

The effect of cone-in-cone insert on the flow pattern of ABS plastic balls in a hopper during their discharging process was studied and simulated with discrete element method. Firstly, the micro parameters of ABS balls were measured and verified by physical experiments. Then the relationship between the structural parameters and the flow pattern was studied via orthogonal experiments, and the distribution of compressive force on the hopper wall analyzed. The results show that the angle of cone-in-cone insert has the most important effect on the flow pattern, the second one is the distance between the cone-in-cone insert and discharge outlet, and the third is the height of the insert. The funnel flow can not change into mass flow when the angle of cone-in-cone insert is smaller than 120o. With the appropriate cone-in-cone insert fixed in the hopper, the maximum compressive force on the hopper wall is reduced to the half of its original value, and its location moves up.