基于离散元法的糙米匀料盘仿真优化设计  

Simulation and optimal design of uniform plate of brown rice based on discrete element method

作　　者：贾富国[1] 姚丽娜[1] 韩燕龙[1] 王会[1] 史宇菲[1] 曾勇[1] 蒋龙伟 

机构地区：[1]东北农业大学工程学院,哈尔滨150030

出　　处：《农业工程学报》2016年第4期235-241,共7页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金项目(51575098);黑龙江省自然科学基金资助项目(E201322);哈尔滨市应用技术研究与开发项目(优秀带头人)(2013RFXXJ086);哈尔滨市应用技术研究与开发项目(2013DB2BG005)

摘　　要：为提高糙米调质过程中的加湿均匀性,在现有匀料技术的基础上,设计了一种曲面式匀料盘。采用离散元法建立匀料盘仿真模型,分析了匀料盘结构参数及运行条件对料层厚度均匀度的影响规律,结合响应面分析法得到各因素的最优组合。仿真结果表明:曲面形式(抛物线系数)对糙米的分布影响极显著(P<0.01),进料量(导流管直径)对糙米的分布影响显著(P<0.05),匀料盘转速对糙米分布影响不显著(P>0.05);综合考虑匀料要求,确定最优结构参数为:匀料盘抛物线方程系数为0.02、导流管与匀料盘直径比为0.1875,最佳运行条件转速为183 r/min,此时料面厚度变异系数可达4.42%。仿真结果与验证结果基本一致,相对误差为2.62%,证明离散元单元法仿真分析曲面式匀料盘工作性能的可行性。Humidifying evenly is the key to moisture conditioning technology. The uniformity of moisture content depends on the material distribution uniformity. Material uniform plate is the chief work part for increasing the material uniformity, and it has an immediate influence on the follow-up material processing quality and production efficiency. In order to improve the humidifying uniformity in the process of brown rice moisture conditioning, a new type of plate called curved-surface material uniform plate was designed on the basis of existing technology. Combined with the material movement rule on the cone material uniform plate, the parabola was set as the curved generatrix of curved-surface material uniform plate. One of the characteristics of the curved-surface material uniform plate was that it enhanced the uniformity of the material thickness by controlling the floating velocity of the material and offered a favorable condition for uniform humidification of brown rice, and moreover it couldn’t damage brown rice. In this study, on the basis of the theoretical analysis, the working process of the curved-surface material uniform plate was simulated with the discrete element method （DEM）, and it was found that the structure parameters and operating conditions of curved-surface refining plate were the key factors affecting its wok performance through the analysis based on the orthogonal design. DEM is a numerical method used for modelling the mechanical behavior of granular materials. Using the EDEM software, the influence laws of the rotation rate of material uniform plate, the curved-surface form and the feeding rateon the material thickness uniformity were simulated and analyzed. According to the performance evaluation indices of evenly distributing material, the structure of curved-surface material uniform plate was optimized. By the response surface analysis method, the mathematical model between each factor and coefficient of variation was established. The validation test was used to verify the availabili

关 键 词：计算机仿真 优化 设计 曲面式匀料盘 离散单元法 

分 类 号：S226.9[农业科学—农业机械化工程]