摘要
应用湍流模型和流体体积模型方法对液滴在低温低速烟气中的破碎特性进行数值研究,重点分析液滴韦伯数和雷诺数对液滴破碎方式的影响,以及烟气密度、流速、液滴速度和粒径等对液滴破碎时间的影响。计算结果表明:对于文中研究的低温低速气体环境及液滴,主要存在液滴发生袋式破碎及没有发生破碎两种形式,临界韦伯数为10.6。韦伯数是液滴破碎的尺度,雷诺数在液滴破碎中不是关键因素。对于文中的气体环境和液滴,综合影响下液滴无量纲破碎时间为常数1,独立于液滴粒径。在文中低温低速气体环境中,将液滴粒径控制在0.3~0.4 mm有助于缩短液滴的完全蒸发时间,提高液滴群蒸发效率。
In this paper,the volume of fluid(VOF)method and a turbulent model were employed to study the character of the drop breakup in the low temperature and low velocity flue gas numerically.The effects of We and Re number on breakup mode were analyzed.The effects of flue gas density and velocity,droplet velocity and diameter on breakup time were also analyzed.The results show that there are two kinds of breakup manner,that are the big breakup process and no breakup process with regard to the gas and droplet studied.The critical Weber number equals to 10.6.In the atmosphere considered,the Weber number is a rule of the droplet breakup,and the Re number is not a critical factor in the process of the liquid drop breakup.Considering the integrated factors,the normalized breakup time of droplet is independent of the droplet diameter,revealing constant 1,within the range of the gas and the droplet studied.In the low temperature and low velocity gas considered,it can conduce to the shorter life time of drop during the evaporation that controls the drop diameter within the range of 0.3~0.4 mm,therefore improving the evaporation efficiency of the drop group.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2012年第5期78-85,共8页
Proceedings of the CSEE
基金
重庆市科委自然科学基金项目(CSTC2008BB6054
CSTC2006BA7035)
"211"工程三期建设项目(S-09101)~~
关键词
液滴破碎
流体体积模型方法
低速烟气
临界韦伯数
liquid droplet breakup
the volume of fluid method
the low velocity flue gas
critical Web
作者简介
张志荣(1975-),女,博士研究生,主要研究方向为气液两相流动与传热;
冉景煜(1968-),男,教授,博士生导师,主要从事先进能动系统转换与利用,燃烧与环保方面的教学与研究工作,ranjy@cqu.edu.cn。