高炉鼓风脱湿系统除雾器挡板结构两相流场数值模拟
2016-06-01罗雨慧谢建中左可
罗雨慧 谢建中 左可
摘要:
对高炉鼓风脱湿系统除雾器的除雾机理进行了详细分析,在此基础上参考实际运行参数,采用计算流体力学(CFD)方法对除雾器挡板结构内的气液两相流动进行了数值模拟,得到了液滴的运动轨迹以及液滴质量浓度、压力、速度和旋涡分布情况,并对除雾器挡板结构内部两相流场进行了深入分析.结果表明:鼓风脱湿系统除雾器能够对携雾气流中的液滴进行有效的分离,从而保证鼓风脱湿系统连续可靠地运行.研究对除雾器的优化设计和运行具有指导意义.
关键词:
除雾器; 鼓风脱湿; 两相流; 压降; 流场
中图分类号: TQ 051.8文献标志码: A
Abstract:
Based on the analysis of the demisting mechanism of the demister in the blower dehumidification system of a blast furnace,the computational fluid dynamics(CFD) method was used to simulate numerically the twophase flow of the gas and liquid in the baffle structure of a demister with the actual operation conditions as a reference.The detailed distributions of the pressure,velocity,vortex,and droplet concentration were provided.The simulation also showed the tracks of the droplets.In addition,an indepth analysis and research on the twophase flow were conducted.The results showed that the demister could separate the droplets from the airflow effectively,so as to ensure that the blower dehumidification system could run continuously and reliably.This study is helpful to the optimization and operation of the demister.
Keywords:
demister; blast dehumidification; two phase flow; pressure drop; flow field
钢铁企业高炉鼓风站的电能消耗十分巨大,其中,鼓风脱湿系统中除雾器阻损对鼓风机的电能消耗影响较大[1].高炉鼓风系统设置的除雾器主要用于清除由鼓风冷凝时产生的游离雾滴,提高鼓风质量.
本文拟对鼓风脱湿系统中丝网与挡板组合式除雾器的分离机理进行详细分析,在此基础上对除雾器挡板结构内部气液两相流动进行数值模拟,得到流道内液滴的运动轨迹及压力、速度、旋涡分布,为除雾器的进一步优化设计提供指导.
1除雾器的结构及工作原理
在脱湿除雾器中,挡板主要起导流作用,究其原因在于多层丝网结构的除雾效率很高(根据现场测试数据,对于粒径大于1 μm的粒子,分离效率高达99%;对于粒径大于2 μm的粒子,分离效率高达99.6%).携雾气流流过丝网结构后……
