带流槽侧壁卸料动态超压及流态的PFC^(3D)数值模拟

THE PFC^(3D) NUMERICAL SIMULATION ON DYNAMIC PRESSURES AND FLOW OF SIDEDRAW SILOS

该文研究一种带流槽侧壁卸料筒仓,该筒仓具有缓解动态超压、基本实现分层有序自动卸料、节约能源等优点。利用PFC^(3D)建立与试验条件相同的三维颗粒流数值模型,模拟静、动态侧压力的大小及分布规律,计算出动态超压系数,并与试验结果进行对比分析。结果表明:卸料口对侧仓壁动态压力较大;最大超压系数达1.4,在所考虑的三列测墙中共有3个位置达到此峰值,其中2个位置发生在卸料口对侧仓壁,而另一个位置发生在距卸料口成90°的仓壁。卸料口对侧仓壁出现2个峰值,一个在筒仓上部0.2 m处,而另一个在筒仓下部0.8 m处;模拟贮料流态和试验吻合较好。

A sidedraw silo with chutes is studied. This silo can effectively reduce the dynamic overpressure and can be able to make stored materials flow in separated layers from top to bottom, thus significant energy can be saved. PFC^3D is used to build a model, which is the same as the test model. The static and dynamic lateral pressures are simulated using this model. The range of the maximum overpressure coefficient is calculated and verified by the test. The results show that the dynamic lateral pressure is lager on the wall which is farthest away from the discharging port and the peak value is 1.4. It also happens in this wall at a 90-degree angle to discharging port. However, there are two peak values on the wall which is farthest away from the discharging port, one is on the upper part and another is on the lower part of the silo wall at a depth of 0.8m. Furthermore, the flow pattern of particles in the numerical simulation is basically identical to that observed in the test.