基于滚动摩擦作用下玉米颗粒在模拟筒仓卸料中的力链分析（网络首发、推荐阅读）

针对颗粒滚动摩擦作用对筒仓中玉米颗粒的力链空间分布进行研究，通过EDEM离散元软件建立筒仓模型与仿真玉米颗粒模型进行卸粮仿真模拟，并与筒仓卸料实验作流态对比，验证模型与仿真结果的准确性。通过对模拟仓进行切片观察和数据处理，对比分析了不同摩擦情况下力链的细观参数随时间演化规律。模拟结果表明：颗粒间摩擦系数越大，卸粮完成的最终时间越长；颗粒间滚动摩擦系数越小，颗粒由整体流转变为管状流的时间越早。对于有漏斗的筒仓来说，减小颗粒间摩擦会改变整体流和管状流之间的极限，从而增加产生管状流的面积。标准滚动摩擦系数下玉米颗粒在卸料过程中会出现起拱-塌陷效应；减小滚动摩擦，玉米颗粒卸料较稳定，未出现起拱的应力突增、以及拱塌陷的应力衰减；增大颗粒间滚动摩擦不但会增加拱效应，且出现成拱高度距离漏斗口更高。

Analysis of Force Chain of Corn Particles in Silo Unloading Based on Rolling Friction(Online First, Recommended Article)

Based on the particle rolling friction, the force chain spatial distribution of corn particles in the silo is studied. The silo model and the corn particle model are established through EDEM discrete element software to simulate the unloading of grain, and the flow pattern is compared with the silo unloading test to verify the accuracy of the model and simulation results. Through slice observation and data processing of the simulated silo, the evolution of the meso-parameters of the force chain with time under different rolling friction conditions are analyzed. The results show that the larger the coefficient of friction between particles, the longer the final time for unloading; the smaller the coefficient of rolling friction between particles, the earlier it takes for the particles to transform from bulk flow to tubular flow. For a silo with a funnel, reducing the friction between particles will change the limit between the bulk flow and the tubular flow, thereby increasing the area where the tubular flow is generated. Under the standard rolling friction coefficient, the corn particles will have the arching-collapse effect during the unloading process. Reducing the rolling friction, the corn particles will be discharged more stable, so there is no sudden increase in the stress of arching nor attenuation in the stress of arch collapse. Increasing the rolling friction between particles will increase not only the feeding effect, but also cause arch height is higher from the funnel mouth.