【摘要】 目前对于斗式提升机卸料状态的研究大多忽略了由于料斗的高速运动而造成的气体流动,及其对于物料颗粒卸料轨迹的影响。采用CFD动网格模拟计算求解以2m/s提升速度运行的斗式提升机内部气流的分布状态,通过CFD-DEM单向耦合方法将流场信息转化为颗粒受力信息并叠加到物料颗粒的离散元仿真计算中,得到考虑气流影响的各尺度下物料颗粒卸料轨迹。研究结果表明,料斗运动所产生的气流造成了物料整体卸料率的下降。使用DEM-CFD单向耦合方法可以得出更为准确的斗式提升机卸料状态描述,从而为斗式提升机的优化设计提供参考。更多还原

【Abstract】 At present, the research on the discharging state of bucket elevator mostly ignores the gas flow caused by the high-speed movement of hopper and its influence on the discharging track of material particles. CFD dynamic grid simulation is used to solve the distribution of air flow in bucket elevator running at a lifting speed of 2 m/s. CFD-DEM one-way coupling method is used to convert the flow field information into particle stress information and superimpose it on the discrete element simulation of material particles to obtain the discharge trajectory of material particles at various scales considering the influence of air flow. The results show that the air flow generated by the hopper movement causes the overall material discharge rate to drop, which is 11.31% lower than that of ignoring the air flow in this study. Air flow has the most obvious effect on small particle materials, resulting in a 10.38%-40.60% drop in the discharge rate of material particles with a particle size ranging from 0.5 mm-1 mm to 1 mm; For medium-sized particles with a particle size of 2-4 mm, the discharging efficiency is reduced by 2.48%-3.55%; However, the discharging process of particles with a particle size larger than 8 mm will not be significantly affected. Using DEM-CFD one-way coupling method, a more accurate description of bucket elevator discharging state can be obtained, thus providing a reference for the optimal design of bucket elevator.更多还原