球磨机磨矿介质动力学数值仿真分析.pdf

学校代号10532学号F1702W0023 分 类 号TB122密级公开 工程硕士学位论文 球磨机磨矿介质动力学数值仿真分析 学位申请人姓名崔振强 培养单位机械与运载工程学院 导师姓名及职称崔向阳教授 田永高级工程师 学科专业机械工程 研究方向（非全日制）机械工程 论文提交日 期2020 年 04 月 20 日 万方数据 学校代号10532 学号F1702W0023 密级公开 湖南大学湖南大学工程工程硕士学位论文硕士学位论文 球磨机磨矿介质动力学数值 仿真分析 学位申请人姓名崔振强 导师姓名及职称崔向阳教授 田永高级工程师 培养单位机械与运载工程学院 专业名称机械工程 论文提交日期 2020 年 04 月 20 日 论文答辩日期 2020 年 05 月 29 日 答辩委员会主席方棋洪教授 万方数据 Numerical simulation analysis of ball mill medium dynamics by Cui Zhengqiang B.E. Nanchang Institute of Technology 2017 Athesis ted in partial satisfaction of the Requirements for the degree of Master of Engineering in Mechanical Engineering in the Graduate School of Hunan University Supervisor Professor Cui Xiangyang Senior engineer TianYong April, 2020 万方数据 工程硕士学位论文 I 湖 南 大 学 学位论文原创性声明 本人郑重声明所呈交的论文是本人在导师的指导下独立进行研究所取得的 研究成果。除了文中特别加以标注引用的内容外，本论文不包含任何其他个人或 集体已经发表或撰写的成果作品。对本文的研究做出重要贡献的个人和集体，均 已在文中以明确方式标明。本人完全意识到本声明的法律后果由本人承担。 作者签名日期2020 年 06 月08 日 学位论文版权使用授权书 本学位论文作者完全了解学校有关保留、使用学位论文的规定，同意学校保 留并向国家有关部门或机构送交论文的复印件和电子版， 允许论文被查阅和借阅。 本人授权湖南大学可以将本学位论文的全部或部分内容编入有关数据库进行检 索，可以采用影印、缩印或扫描等复制手段保存和汇编本学位论文。 本学位论文属于 1、保密□，在年解密后适用本授权书。 2、不保密☑ 。 （请在以上相应方框内打“√”） 作者签名日期2020 年 06 月08日 导师签名日期2020 年 06 月08日 万方数据 球磨机磨矿介质动力学数值仿真分析 II 摘要 球磨机是矿山、陶瓷、水泥等行业中必不可少的磨矿破碎设备，也是上述行 业内的高能耗设备。球磨机每年的耗电总量达到全国发电总量的 5，其如此高 的能耗除了因为庞大的需求量之外，也与其较低的磨矿效率有关。决定球磨机能 耗的主要因素在于研磨介质的运动学行为，然而人们目前还没有完全掌握球磨机 复杂的磨矿行为。本文针对球磨机磨矿介质运动行为问题，利用现有相关软件和 离散元方法，对球磨机磨矿介质运动行为开展研究，旨在寻求球磨机研磨介质的 运动特性和对磨矿过程的影响规律，为提高球磨机磨矿效率和优化现有球磨机工 况参数提供一定的理论和技术依据。 本文主要研究内容包括利用数值模拟方法分析物料在磨矿数值分析中存在 的重要性和必要性；设计物料粒径对研磨介质运动影响的仿真试验，解析物料粒 径的大小对研磨介质运动轨迹影响的变化过程；利用离散元 Hertz-Mindlin with Bonding 接触模型模拟球磨机磨矿破碎过程，解析球磨机磨矿变化特性以及磨矿 中高效破碎区域的分布；开展工况参数对磨矿效率的影响试验，探析转速率、填 充率、提升条高度三种工况参数对球磨机磨矿破碎效率的影响规律。 首先，通过数值模拟，验证本文数值模拟方法的可行性与可靠性，并对比有 无物料两种情况下介质运动轨迹以及速度的差异，指出了物料的存在对研磨介质 的运动产生不可忽视的影响，能使球磨机磨矿数值分析更接近实际情况；同时设 计两组组对照试验，分析了物料粒径对研磨介质影响程度的变化规律，以及提升 条高度对研磨介质运动轨迹产生的影响规律， 确定了物料粒径和提升条尺寸范围。 接着，利用 Hertz-Mindlin with Bonding 接触模型建立了球磨机磨矿过程仿真 试验，得到了磨矿过程中研磨介质运动和磨矿破碎变化规律，同时还结合研磨介 质对物料的作用力分布特性，指出了球磨机高效破碎区域的分布以及破碎特点。 最后，建立多组仿真试验模拟物料破碎过程，得到了三种工况参数对球磨机 磨矿效率的影响特性。试验解析了球磨机转速率、填充率、提升条高度的变化对 球磨机磨矿效率的影响规律以及在磨矿过程中物料破碎速率的变化特性。 本文的研究为球磨机的数值仿真设计提供了参考，对球磨机的设计和磨矿分 析具有重要意义。 关键词球磨机；离散元；破碎；研磨介质 万方数据 工程硕士学位论文 III Abstract Ball mill is an indispensable grinding and crushing equipment in mining, ceramics, cement and other industries, and also a high energy consumption equipment in the above industries. The annual power consumption of the ball mill reaches 5 of the total power generation in the country, and its high energy consumption has caused a huge demand in addition to its low grinding efficiency. The main factor that determines the energy consumption of the ball mill is the kinematic behavior of the grinding media. However, people have not yet fully mastered the complex grinding behavior of the ball mill. Aiming at the motion behavior of ball mill grinding media, this paper uses existing related software and discrete element s to study the motion behavior of ball mill grinding media, aiming to seek the motion characteristics of ball mill grinding media and the changing law of the grinding process, in order to improve the ball mill Grinding efficiency and optimizing the working condition parameters of existing ball mills provide a certain theoretical and technical basis. The main research contents of this article include the numerical simulation proves the importance and necessity of the material in the numerical analysis of grinding; the design of a simulation test of the effect of the particle size of the material on the motion of the grinding medium, and the analysis of the effect of the particle size of the material on the movement path of the grinding medium Change process; using the discrete element Hertz-Mindlin with Bonding contact model to simulate the grinding process of the ball mill, analyze the ball mill grinding characteristics and the distribution of high-efficiency crushing areas in the mill; carry out the test of the influence of the working condition parameters on the grinding efficiency The influence of the three working condition parameters of rotation rate, filling rate and lifting bar height on the grinding efficiency of the ball mill. First of all, the feasibility and reliability of the numerical simulation in this paper are verified by numerical simulation, and the differences of the medium movement track and speed between the two cases of whether there is material or not are compared. It is pointed out that the existence of material has an important influence on the grinding medium movement, which makes the grinding numerical analysis of the ball mill closer to the actual situation. At the same time, two groups of control tests are designed to analyze the material The influence of the particle size on 万方数据 球磨机磨矿介质动力学数值仿真分析 IV the grinding medium and the influence of the height of the lifting bar on the moving track of the grinding medium are determined. Then, using Hertz Mindlin with binding contact model, the simulation test of grinding process of ball mill is established, and the movement of grinding media and the change rule of grinding and crushing are obtained. At the same time, combining the distribution characteristics of the force of grinding media on materials, the distribution of high-efficiency crushing area and crushing characteristics of ball mill are pointed out. At last, a series of simulation tests are set up to simulate the process of material crushing, and the influence characteristics of three working conditions parameters on the grinding efficiency of the ball mill are obtained. The effects of the changes of the ball mill speed rate, filling rate and lifting bar height on the grinding efficiency of the ball mill and the change characteristics of the material crushing rate in the grinding process were analyzed. The research in this paper provides a reference for the numerical simulation design of the ball mill, which is of great significance to the design and grinding analysis of the ball mill. Key WordsBall mill；Discrete element ；Crush；Medium movement 万方数据 工程硕士学位论文 V 目录 学位论文版权使用授权书......................................................................................................I 摘要.......................................................................................................................................II Abstract................................................................................................................................... III 目录.......................................................................................................................................V 插图索引............................................................................................................................... VII 附表索引.................................................................................................................................IX 变量注释表..............................................................................................................................X 第 1 章 绪论.............................................................................................................................1 1.1 课题研究背景及意义............................................................................................ 1 1.2 离散单元法与 EDEM............................................................................................3 1.2.1 离散元基本思想............................................................................................. 3 1.2.2 基本计算方法..................................................................................................4 1.2.3 颗粒计算过程..................................................................................................5 1.3 国内外研究现状.....................................................................................................6 1.3.1 球磨机研磨介质研究现状............................................................................6 1.3.2 离散元在球磨机上的应用............................................................................7 1.4 矿石破碎理论......................................................................................................... 8 1.5 本文研究内容及目标............................................................................................ 9 1.6 本章小结................................................................................................................10 第 2 章 球磨机磨矿模型与仿真基础................................................................................11 2.1 磨矿数学模型....................................................................................................... 11 2.2 无物料磨矿仿真模型的建立.............................................................................15 2.2.1 磨矿参数设定................................................................................................15 2.2.2 磨矿结果验证................................................................................................16 2.3 考虑物料的磨矿仿真模型的建立.....................................................................17 2.3.1 理想性假设....................................................................................................17 2.3.2 磨矿介质类型................................................................................................17 2.3.3 介质类型选择................................................................................................17 2.3.4 介质尺寸选择................................................................................................23 2.3.5 磨机提升条的重要性...................................................................................27 2.4 本章小结................................................................................................................29 第 3 章 磨矿破碎过程数值仿真求解............................................................................... 31 3.1 引言........................................................................................................................ 31 万方数据 球磨机磨矿介质动力学数值仿真分析 VI 3.2 磨矿模型求解条件...............................................................................................31 3.3 球磨机磨矿结果分析..........................................................................................33 3.3.1 球磨机磨矿过程效率分析..........................................................................35 3.3.2 研磨介质运动轨迹变化规律......................................................................37 3.3.3 球磨机有效破碎区域分析..........................................................................39 3.4 本章小结................................................................................................................41 第 4 章 球磨机磨矿参数仿真分析....................................................................................43 4.1 模型建立................................................................................................................43 4.2 提升条对磨矿破碎的影响规律.........................................................................44 4.3 填充率对磨矿破碎的影响规律.........................................................................46 4.4 转速率对磨矿破碎的影响规律.........................................................................48 4.5 本章小结................................................................................................................50 结论与展望.............................................................................................................................52 参考文献.................................................................................................................................54 致谢..................................................................................................................................... 58 万方数据 工程硕士学位论文 VII 插图索引 图 1.1球磨机磨矿示意图...................................................................................................1 图 1.2球磨机分区和运动分布图......................................................................................2 图 1.3离散单元法计算过程图..........................................................................................5 图 1.4颗粒接触示意图.......................................................................................................5 图 2.1颗粒粘结半径.........................................................................................................14 图 2.2仿真验证对比.........................................................................................................16 图 2.3介质运动状态轨迹图............................................................................................19 图 2.4提升条 15mm 研磨介质运动状态图.................................................................. 20 图 2.5无物料的介质数量-速度柱状图..........................................................................21 图 2.6有物料的介质数量-速度柱状图..........................................................................21 图 2.7介质位置分布.........................................................................................................22 图 2.8不同物料的粒径磨矿过程图............................................................................... 24 图 2.9不同粒径的研磨介质轨迹图............................................................................... 25 图 2.10物料运动轨迹图...................................................................................................26 图 2.11研磨介质运动轨迹随提升条变化规律............................................................28 图 2.12物料运动轨迹随提升条变化规律.....................................................................28 图 3.1物料颗粒转变过程.................................................................................................32 图 3.2颗粒群破碎过程.....................................................................................................32 图 3.3物料位置获取过程.................................................................................................33 图 3.4颗粒替换过程.........................................................................................................34 图 3.5磨矿时刻状态.........................................................................................................34 图 3.6物料粘结键时间-破碎量曲线..............................................................................36 图 3.7一阶导数曲线图.....................................................................................................36 图 3.8研磨介质磨矿轨迹图............................................................................................37 图 3.9研磨介质计数区域划分........................................................................................38 图 3. 10研磨介质不同区域数量分布............................................................................38 图 3.11介质与物料作用力区域分布.............................................................................40 万方数据 球磨机磨矿介质动力学数值仿真分析 VIII 图 3.12介质动能区域分布.............................................................................................. 41 图 4.1不同衬板参数下颗粒破碎曲线45 图 4.2不同衬板参数下颗粒破碎曲线...........................................................................45 图 4.3磨矿曲线..................................................................................................................46 图 4.4不同填充率颗粒破碎曲线.................................