摘要
为了解溜井内颗粒物料运动特征,利用颗粒离散元方法和Hertz-Mindlin非线性接触模型,考虑井壁形貌特征和溜放矿块粒级组成,建立了井壁起伏差服从正态分布的非光滑井壁溜井和铲运机球形随机颗粒群放矿数值分析模型,用该模型对溜井不同区段内颗粒群碰撞及运动规律统计特征展开了分析。结果表明:(1)颗粒对溜井壁的碰撞源于颗粒脱离铲斗时速度的不一致性,碰撞自井口开始至井深-18～-30 m处达到碰撞频数最高值;(2)颗粒碰撞频发区为井口以下至2/3井深,该区域内颗粒的平均速率低且变化较小,井壁受损程度主要受颗粒对井壁碰撞频数影响,此后颗粒平均速率快速增长;(3)铲斗翻转速度对颗粒碰撞井壁的频数和平均速率的影响不明显,减缓铲斗翻转速度致使颗粒对井壁的碰撞集中区域下移;(4)井壁两侧受碰撞的频数变化受井壁起伏差影响较大,且碰撞总频数随井壁起伏差的增加而增多。
In order to understand the movement characteristics of granular matters in the ore pass,a numerical analysis model of the non-smooth wall pass,in that the difference of shaft fluctuation will obey Gaussian distribution,and the scraper spherical stochastic particle group drawing was established by using particle discrete element method and Hertz-Mindlin nonlinear contact model,and considering the characteristics of shaft wall morphology and the composition of ore-drawing blocks.The statistical characteristics of collision and movement of particle groups in different sections of the chute were analyzed. The results showed that:(1) the collision of particles on the chute wall is due to the inconsistency of velocity when the particles leave the bucket,and the collision frequency reaches the highest value from the wellhead to the depth of-18 m to-30 m;(2)the frequent occurrence area of particle collision is below the wellhead and extending to the depth of 2/3 well,the average velocity of particles in this area changes a little,and the damage degree of the wellbore is mainly affected by the collision frequency of the particles. After that,the average velocity of particles increases rapidly;(3) the bucket rotation speed has less impact on the collision frequency and average velocity of particles on the wellbore,slowing bucket rotation speed can move the particles downward the collision concentration area;(4)the frequency variation of collision on both sides of the wellbore is affected by the fluctuation difference of the wellbore. The total frequency of collision increases with the increase of the fluctuation difference.
作者
韩连生
杨宇江
Han Liansheng;Yang Yujiang(Gongchangling Mining Company of Ansteel Group Corporation,Liaoyang 111008,China;School of Mining Engineering University of Science and Technology Liaoning ,Anshan 114051,China)
出处
《金属矿山》
CAS
北大核心
2019年第1期40-48,共9页
Metal Mine
关键词
运动特征
碰撞
颗粒介质
离散元
溜井
Movement features
Impact
Granular matter
Discrete element
Ore pass
