蒸汽相变促进烟气中细颗粒生长的数值模拟  

Numerical simulation of fine particles in flue gas by using of vapor phase change

作　　者：梅涛 李阳[1] 杨历[1] 陈占秀[1] MEI Tao;LI Yang;YANG Li;CHEN Zhanxiu(School of Energy and Environmental Engineering,Hebei University of Technology,Tianjin 300401,China)

机构地区：[1]河北工业大学能源与环境工程学院

出　　处：《河北工业大学学报》2019年第3期27-33,共7页Journal of Hebei University of Technology

基　　金：河北省高等学校科学技术研究项目(ZD2015128,ZD2016163);河北工业大学能环学院动力工程领域专业学位研究生创新项目

摘　　要：利用气相与颗粒相耦合模拟计算烟气中细颗粒的生长情况,其中气相采用的是湍流模型中的k-ε模型,颗粒相采用的是颗粒群平衡模型(Population Balance Model,PBM),在流动过程中通过固液两相间的相互作用将两相耦合。分析了相同初始过饱和度下不同温度的含尘烟气对异质成核过程中管内过饱和度及粒径分布的影响;并研究不同初始饱和度、颗粒在生长管内的停留时间以及生长管壁温对管内细颗粒异质成核的影响。结果表明:温度升高会导致管内过饱和度降低,异质成核的速率下降;初始饱和度越大,管内过饱和环境充分,有利于细颗粒生长;细颗粒在生长管内停留的时间越长,异质成核作用越充分,有利于细颗粒的生长;生长管内的壁温低于烟气温度时,管内过饱和度越大,促进细颗粒的生长。The growth of fine particles size in flue gas was investigated by coupling simulation of gas-phase and particle phase.In the simulation process,gas-phase was solved by using k-εmodel of the turbulent model,and particle phase was solved by using population balance model,and finally the couple of gas-particle phase was linked by interaction of the phases.It was analyzed that the distribution of supersaturation and particle size in the same initial supersaturation and different temperature of the flue gas,which is in the progress of the heterogeneous nucleation.It was also analyzed the effect of the fine particles heterogeneous nucleation in different initial supersaturation,residence time of the particles in the growth tube,and the wall temperature of the growth tube.The results show that the increase of temperature of flue gas would lead to the decrease of supersaturation in the growth tube,and cause the decrease of heterogeneous nucleation rate;Higher initial supersaturation and better environment of the supersaturation in the tube are good for the growth of fine particles.The longer time the fine particles stay in the tube,the better reaction of the heterogeneous nucleation will be,which is good for the growth of fine particles.When the wall temperature is lower than the gas temperature,the super.saturation of the growth tube would be larger,and it would promote the growth of fine particles.

关 键 词：异质成核 颗粒群平衡模型 湍流模型 过饱和度 

分 类 号：X513[环境科学与工程—环境工程]