摘要
采用数值模拟的方法对垂直下降管内液膜沸腾蒸发流动和传热特性进行研究。分析入口雷诺数Re和热流密度的耦合作用对液膜流动和传热的影响,结果表明:壁面生成的汽泡呈现液滴状;大汽泡表面分割、脱离出小汽泡;汽泡生成、脱离强化了沸腾传热效率;热流密度越大,液膜表面的稳定性越差;Re的提高能够增强相界面稳定性;降膜沸腾传热方式的不同对传热系数影响很大;在计算工况范围内,绘制出传热模态分布图,为工程应用提供基础。
The flow and heat transfer characteristics of liquid film boiling in vertical dropping tubes were studied by numerical simulation. The effects of Reynolds number and heat flux on the flow and heat transfer of the liquid films were analyzed. The results show that the bubbles produced by the wall are droplet-like,the big bubble surface is separated into small bubble,the bubble generation and detachment enhances the boiling heat transfer efficiency. The greater the wall heat flux,the more unstable the liquid film surface. The increase of the Reynolds number can enhance the interfacial stability. Different heat transfer modes have a great influence on the heat transfer coefficient. Finally,the distribution pattern of falling film heat transfer is drawn according to the calculation conditions,which is convenient for engineering application.
作者
范学成
张琳
卜诗
许伟刚
柳林
章征敏
Fan Xuecheng;Zhang Lin;Bo Shi;Xu Weigang;Liu Lin;Zhang Zhengmin(School of Mechanical Engineering,Changzhou University,Changzhou 213016,China;Jiangsu Key Laboratory of Green Process Equipment,Changzhou 213164,China)
出处
《太阳能学报》
EI
CAS
CSCD
北大核心
2019年第8期2258-2265,共8页
Acta Energiae Solaris Sinica
基金
江苏省高等学校自然科学研究重大项目(18KJA480002)
江苏省“六大人才高峰”创新人才团队项目(GDZB-CXTD-001)
国家青年自然科学基金(51606014)
江苏省青年自然科学基金(BK20160281)
常州市重点研发计划(社会发展科技支撑)项目(CE20180322)
关键词
降膜
沸腾蒸发
流动特性
传热特性
数值模拟
vertical falling film
boiling evaporation
flow characteristics
heat transfer characteristics
numerical simulation
