廖贵文,姜永正,胡亚凡,朱升硕,苗晶晶,桂建新
（湖南科技大学 机械设备健康维护湖南省重点实验室,湖南 湘潭 411201）
DOI：10.13732/j.issn.1008-5548.2021.01.009
收稿日期：2020-08-03,修回日期：2020-09-30，在线出版时间：2020-11-02 10:31。
基金项目：国家自然科学基金项目，编号：51705143；湖南省自然科学基金项目，编号：2018JJ3164。
第一作者简介：廖贵文(1993—)，男，硕士研究生，研究方向为散体动力学建模。E-mail:1017405297@qq.com。
通信作者简介：姜永正(1984—)，男，博士，副教授，硕士生导师，研究方向为复杂高端装备(散体输送、水下及海上装备)的耦合建模。
摘要：表面能为湿煤颗粒含水率的表征参数。为解决在离散元仿真模拟中非球形湿煤颗粒表面能的设置问题，首先通过圆筒法测量不同含水率的9种煤料的堆积角，研究堆积角与含水率间之间的关系;随后利用EDEM进行圆筒堆积仿真试验，建立堆积角与表面能之间的线性回归模型;最后运用回归分析法建立含水率与表面能之间的二次多项式回归数学模型。结果表明:粒径为3～5 mm的湿煤料颗粒的堆积角随着含水率增加而增加;表面能为0～2 J/m2时堆积角随表面能呈线性缓慢增大趋势;表面能为2～3.75 J/m2时堆积角随表面能快速增大;基于表面能的非球形湿煤散料颗粒含水率的数学模型与实验结果的最大误差小于2%，说明表征方法准确可靠。由数学模型测算可知:当含水率≤10%时，表面能随含水率快速增大;当煤料含水率>10%时，表面能随含水率增大的趋势趋于平缓。
关键词：湿煤颗粒；含水率；表面能；堆积角；回归分析
Abstract：Surface energy is the characterization parameter of moisture content of wet coal particles. In order to solve the problem of setting the surface energy of non-spherical wet coal particles in the discrete element simulation,the accumulation angle of 9 kinds of coal with different moisture content was firstly measured by cylinder method so as to study on the relationship between accumulation angle and moisture content. And then EDEM was used to carry out a simulation test of cylinder stacking and establish a linear regression model between stacking angle and surface energy. Finally,the regression analysis method was used to establish a second-degree polynomial regression mathematical model between the moisture content and the surface energy. The results show that the stacking angle of wet coal particles with a particle size of from 3 to 5 mm increases with the increase of water content,and when the surface energy is from 0 to 2 J/m2,the stacking angle increases slowly with the surface energy. When the surface energy is from 2 to 3. 75 J/m2,the stacking angle increases rapidly with the surface energy. The maximum error between the mathematical model of the moisture content of non-spherical wet coal bulk particles based on surface energy and the experimental results is less than 2%,indicating that the characterization method is accurate and reliable. Calculations from the mathematical model show that when the water content is less than or equal to 10%,the surface energy increases rapidly with the water content; when the coal water content is greater than 10%,the trend of the surface energy increasing with the water content tends to be gentle.
Keywords：wet coal particle; moisture content; surface energy; stacking angle; regression analysis
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