滚筒干燥机内煤粉尘颗粒传热传质数值模拟

Study on the influence of boundary condition on heat and mass transfer of coal slime particles in a drum dryer

为了研究干燥介质流量和温度对滚筒干燥机内煤泥干燥的效果,提高工业生产效率并保障系统的安全性,利用流体仿真Fluent软件对滚筒干燥机内煤泥热烟气干燥过程进行了数值模拟。采用Rosin-Rammler模型对颗粒粒度分布进行定义。通过改变烟气的物理参数,分析系统内煤泥颗粒干燥情况与干燥介质流量、温度之间的关系。结果表明,煤泥干燥效率随着入口烟气温度的增高而提高,但较高的烟气温度也会造成更多的热损耗,较高的烟气速率一定程度上可以提高,但也会带走热量。工业生产在安全范围内,达到生产需求的情况下,烟气温度和速率都不宜过高。

In order to study the effects of drying medium flow rate and temperature on coal slime drying in a drum dryer,improve the industrial production efficiency and ensure the safety of the system,the drying process of coal slime with hot flue gas in drum dryer is numerically simulated with Fluent software.Rosin-Rammler model is used to define the particles size distribution.By changing the physical parameters of flue gas,to analyze the relationship on the drying condition of coal slime particles with the flow rate and temperature of drying medium in the system.The results show that the drying efficiency of slime increases with the increase of inlet flue gas temperature,but higher flue gas temperature also leads to more heat loss.The temperature and rate of flue gas should not be too high when the industrial production is within the safe range.