六棱柱滚筒冷渣机传热效率影响  

Heat Transfer Efficiency of Slag Cooler Based on Hexagonal Cylinder

作　　者：赵飞 王佳 何庆中 何涛 王漫漫 ZHAO Fei;WANG Jia;HE Qing-zhong;HE Tao;WANG Man-man(School of Mechanical Engineering,Sichuan University of Light Chemical Technology,Yibin 644000,China)

机构地区：[1]四川轻化工大学机械工程学院,宜宾644000

出　　处：《科学技术与工程》2022年第27期11924-11932,共9页Science Technology and Engineering

基　　金：四川省教育厅创新团队项目(17TD0026);自贡市科技局项目(2018YYJC08);四川轻化工大学重点项目(2018RCL12)。

摘　　要：冷渣机是CFB(circulating fluidized bed)锅炉的重要辅机,其传热效率对CFB锅炉的连续稳定运行发挥着重要作用。为了进一步分析颗粒传热效率的关系,以一种多管式六棱柱滚筒冷渣机为研究载体,以冷渣管内高温灰渣颗粒为研究对象,基于离散元方法及其数值模型,运用商用软件EDEM来模拟分析高温灰渣颗粒在冷渣管内的传热过程。将颗粒温度规范化处理为无量纲温度,以平均温度、温度概率密度函数和颗粒运动规律为指标定量分析滚筒转速和颗粒直径对灰渣颗粒传热过程的影响。其中,六棱柱冷渣管边长200 mm、长500 mm、壁厚10 mm,管初始温度360 K,颗粒初始温度1 200 K。结果表明:颗粒的传热效率随着转速的增大而增大,转速为10 r/min相对于转速为4 r/min的散热效率增加了61.1%;颗粒的传热效率随着粒径的增大而减小,粒径为5 mm相对于粒径为3 mm的散热效率下降了30.7%。转速是通过翻转次数来影响传热效率,粒径是通过影响接触点碰撞次数来影响传热效率。Slag cooler is an important auxiliary machine of CFB(circulating fluidized bed) boiler, its heat transfer efficiency plays an important role in the continuous and stable operation of CFB boiler. In order to further analyze the relationship between particle heat transfer efficiency, based on the discrete element method and its numerical model, the heat transfer process of high temperature ash particles in the cold slag tube was simulated and analyzed by using the commercial software EDEM. The particle temperature was normalized to dimensional temperature, and the effects of roller speed and particle diameter on the heat transfer process of ash particles were quantitatively analyzed by taking the average temperature, temperature probability density function and particle motion law as indexes. Among them, the side length of hexagonal cold slag tube was 200 mm, the length was 500 mm, the wall thickness was 10 mm, the initial temperature of tube was 360 K, and the initial temperature of particle was 1 200 K. The results show that the heat transfer efficiency of particles increases with the increase of rotating speed, and the heat transfer efficiency of 10 r/min is 61.1% higher than that of 4 r/min. The heat transfer efficiency of particles decreases with the increase of particle size. The heat transfer efficiency of 5 mm is 30.7% lower than that of 3 mm. The rotational speed affects the heat transfer efficiency by the number of turns, and the particle size affects the heat transfer efficiency by the number of collisions at the contact point.

关 键 词：滚筒冷渣机 EDEM 颗粒传热 传热效率 颗粒运动 

分 类 号：TK229.6[动力工程及工程热物理—动力机械及工程]