水平管排外降膜蒸发换热特性  

Evaporation Heat Transfer of Falling Liquid Films on Horizontal Tube Arrays

作　　者：刘振华[1] 朱群志[1] 陈玉明[1] 

机构地区：[1]上海交通大学动力与能源工程学院,上海200030

出　　处：《上海交通大学学报》2000年第4期478-481,485,共5页Journal of Shanghai Jiaotong University

摘　　要：采用层流和紊流两种模型对水平管外垂下液膜的强制对流蒸发换热性能进行了数值计算 .计算中 ,对管顶部的冲击滞止区和管侧部的自由绕流区分别采用不同的坐标变换方法进行微分方程组简化 .根据滞止区计算结果确定自由绕流区的初始边界条件 ,排除了以前类似计算中人为假定计算边界条件的缺陷 .紊流计算采用壁面函数法 .计算结果和作者的单管和管排实验数据及其他研究的实验数据进行了比较 ,结果表明 ,实验值处于层流解和紊流解之间 ,更靠近紊流解 .实验证明 ,单管和三管管排的平均换热系数十分接近 。Numerical analyses and experiments were carried out to obtain the evaporating heat transfer characteristics of falling film on horizontal heated single tube and tube arrays. Liquid flow region was divided as stagnation zone and free surface flow zone and two kinds of coordinate transformations were used to simplify the governing equations of the two zones. Both of laminar and turbulent models were adopted for free surface flow respectively. Numerical solutions were compared with the experimental data and it is confirmed that the turbulent flow solutions agree well with the experimental results of ours as well as other researcher's. A dimensionless formula is correlated by use of turbulent flow numerical solutions of single tube and it can too apply to the tube arrays approximately.

关 键 词：蒸发 降膜 水平管排 换热特性 垂下液膜 

分 类 号：TK124[动力工程及工程热物理—工程热物理] TK172[动力工程及工程热物理—热能工程]