中国电机工程学报2017，Vol.37Issue(6)：1731-1738,8.DOI:10.13334/j.0258-8013.pcsee.152556
竖直热壁冷却下降液膜瞬变传热及相界面波动
Transient Heat Transfer and Phase Interface Wave of Falling Liquid Film When Cooling Vertical Heated Surface
摘要
Abstract
Transient numerical analysis on flowing process of free-falling liquid film when cooling vertical heated surface with constant heat flux are performed.The numerical model and physical model are developed for simplified two-dimensional flow.Employing RNG k-ε to calculate vapor liquid two phase turbulent flow.The multiphase model volume of fluid (VOF) is used to predict heat and mass transfer combining with user defined function.Distribution law for thickness of liquid film along heated surface under different cases are obtained.Numerical results indicate that phase interface of liquid film waves in different degrees and different styles during flow cooling.Stability of liquid film phase interface becomes weak due to thermal disturbance,however,it can be improved by increasing inlet mass flux.These two factors are reciprocal inhibition with regard to flow stability of liquid film.Movement and transformation of bubbles in liquid film affect wave of liquid film phase interface significantly during nucleate boiling.On the basis of transient numerical results,variation trends of surface heat transfer coefficient are same for different cases.Thermal stability of liquid film are coupling effected by flow disturbance and thermal disturbance.Basing on gas-liquid two phase flow and heat transfer characteristics,reasons of phenomenon appeared is analyzed.关键词
竖直热壁/下降液膜/汽泡/波动/两相流/数值分析Key words
vertical heated surface/falling film/bubbles/wave/two-phase flow/numerical analysis分类
能源科技引用本文复制引用
黄娜,周云龙,李洪伟,高聚,Kambiz Vafai..竖直热壁冷却下降液膜瞬变传热及相界面波动[J].中国电机工程学报,2017,37(6):1731-1738,8.基金项目
国家自然科学基金项目(51406031).Project Supported by National Natural Science Foundation of China (51406031). （51406031）
