离散元法之振动磨介流数值模拟与试验  

Discrete element on the numerical simulation and experiment of vibration grinding medium flow

作　　者：杨小兰[1,2] 刘极峰[2,1] 周亚军[2] 王治金[1] 

机构地区：[1]南京工程学院机械工程学院,江苏南京211167 [2]黄河科技学院工学院,河南郑州450015

出　　处：《振动工程学报》2016年第3期479-487,共9页Journal of Vibration Engineering

基　　金：国家自然科学基金资助项目(51375221);河南省重点科技攻关计划(142102210138);郑州市科技攻关计划(20130797);国家级大学生创新创业训练计划项目资助(201511276005Z)

摘　　要：为研究磨介细观运动过程及粉碎机理,构建基于离散元法之振动磨磨介流数值模拟模型,按频幅大小设定两种振强等级、4种模式的工况组合,导出筒体运动方程,求得筒体中心运动轨迹、磨介流速矢场、速度云图等真实运动,数值模拟结果表明:相对其他模式,C模式(中频高幅)乏能区至少减小8%,筒内前端磨介动能分别为其他模式的1.26~22.31倍,其动能增加使得磨介间撞击效果强,为超微颗粒细化试验的参数优化提供了富有价值的参考;在普通和新型振动磨上分别进行试验,经激光粒度仪检测、高速摄影机记录,分别取得d(50)=1.6,0.2μm、带宽4.8,0.3μm的检测结果,明显体现出新型振动磨颗粒细化和带宽窄化效果,成为超硬超微粉体细化方面的技术试验实证。In order to research the mesoscopic movement process and the mechanism of smashing,a numerical simulation model of the vibration grinding medium flow is built based on discrete element theory.According to various amplitude and frequency combinations,the vibration intensity is divided into two levels in four models,and the equation of the motion is derived.Consequently,the motion trajectory of the barrel center,the vector field of the grinding medium flow and the cloud picture of speed are all obtained.The results show that in mode C(mid-frequency with high-amplitude)the energy lacking area is reduced to at least 8%.The kinetic energy of the medium flow in the front part inside the barrel is equivalent to 1.26 to 22.31 times of other modes.The increase of the kinetic energy makes the impact among the media more effective,and hence provides a valuable reference to the study of test parameter optimization in superfine grain refinement process.Experiments are conducted on both the regular and the newly developed grinding millsand the results recorded by laser particle size analyzer and high speed camera show that the refinement of particles is from d(50)= 1.6mdown to 0.2mand the band width is narrowed from 4.8mto 0.3m.This can serve as evidence on super-hard superfine powder refining technology advancement.

关 键 词：磨介流 离散元法 数值模拟 振强等级 试验比对 

分 类 号：TQ051.9[化学工程]