梅 潇, 田 源, 刘祥伟

（上海海事大学物流工程学院, 上海201306）

引用格式：梅潇, 田源, 刘祥伟. 超微粉碎机的物料粉碎分级实验与仿真分析[J]. 中国粉体技术, 2023, 29(6): 72-81.

MEI X, TIAN Y, LIU X W. Experiment and simulation analysis of material crushing and classification of ultrafine pulverizer[J]. China Powder Science and Technology, 2023, 29(6): 72-81.

DOI：10.13732/j.issn.1008-5548.2023.06.007

收稿日期：2023-05-16,修回日期：2023-09-15,在线出版时间：2023-10-16 15:20。

基金项目：上海市科委浦江人才计划项目,编号:21PJ1404600。

第一作者简介：梅潇(1974—),女,副教授,博士,硕士生导师,研究方向为结构设计与安全评估、现代设计方法以及多相场仿真和实验。E-mail: xiaomei@shmtu.edu.cn。

摘要：为了获得超微粉碎机最优的粉碎效果并保证出料颗粒细微且均匀,在一定的刀盘转速条件下使用超微粉碎机进行粉碎实验;为了优选喂料频率,分析不同喂料频率对刀盘粉碎效果的影响;对比试样的粒径分布,分析刀盘和分级轮对物料的粉碎与分级效果;采用Fluent软件将超微粉碎机内部流场可视化,分析不同分级轮转速条件下物料在出料口的质量流率分布以及分级区域的流场状态。结果表明:当刀盘转速为1 232 r/min时,喂料频率对颗粒粒径的分布影响较小,优选喂料频率为20 Hz;分级轮转速对粒径>40 μm的颗粒的分级效果的影响更大,但对粒径>0.5～40 μm的颗粒的分级影响较小;随着分级轮转速的增大,物料出口处的细颗粒含量增大,粒径减小;当刀盘转速为1 232 r/min、分级轮转速为900 r/min时,粉碎腔内部的速度等值线分布最均匀而且流体流动平稳,切向速度与压力分布的对称性最好,气流在轴向方向上整体表现为上升运动,有利于物料稳定地出料;较优分级轮转速为900 r/min。

关键词：超微粉碎; 气-固两相流; 颗粒分级; 分级轮转速; 数值模拟

Abstract：In order to obtain the best crushing effect of the ultrafine pulverizer and ensure the fine and uniform discharge particles, the ultrafine pulverizer was used for crushing experiments under a certain cutter head speed. In order to optimize the feeding frequency, the influence of different feeding frequency on the crushing effect of cutter head was analyzed. By comparing the particle size distribution of experimental samples, the crushing and grading effect of cutter and grading wheel were analyzed. Fluent software was used to visualize the flow field inside the ultrafine pulverizer, and the mass flow rate distribution of materials at the discharge port and the flow field state in the grading region were analyzed under different grading wheel speeds. The result shows that when the cutter speed is 1 232 r/min, the feeding frequency has little influence on the particle size distribution, and the optimal feeding frequency is 20 Hz. The rotating speed of the grading wheel has greater effects on the grading effect when the particle size is more than 40 μm, but has less effects when the particle size of is from 0.5 to 40 μm. With the increase of the rotation speed of the grading wheel, the content of fine particles at the outlet of the material increases and the particle size decreases. When the cutter speed is 1 232 r/min and the grading wheel speed is 900 r/min, the velocity contour distribution in the crushing chamber is the most uniform and the fluid flow is stable, the symmetry of tangential velocity and pressure distribution is the best, and the air flow shows an overall upward movement in the axial direction, which is conducive to the stable discharge of materials. The optimal rotational speed of the grading wheel is 900 r/min.

Keywords：ultrafine pulverization; gas-solid two-phase flow; particle classification; rotational speed of grading wheel; numerical simulation

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