窄通道中过冷沸腾汽-液界面凝结换热系数

Condensation Heat Transfer Coefficient at Vapour-Liquid Interface of Subcooled Flow Boiling in Vertical Narrow Rectangular Channel

采用高速摄像仪以5000 fps的拍摄速度对竖直矩形窄缝流道内过冷沸腾的汽泡凝结过程进行可视化研究,结合相应的理论分析,并考虑对流换热以及热边界层增厚对凝结换热的影响,得到了无量纲汽泡直径β和界面凝结换热努塞尔特数Nu及其影响因素之间的关系式。与实验数据比较,预测误差在±25%以内。

High speed camera visualized subcooled flow boiling bubble condensation experiments at 5 000 fps were conducted. Combined with the theoretic analysis, and considering the effect of convective heat transfer and the thickness of thermal boundary layer on condensation heat transfer, the relationship be- tween dimensionless bubble diameter β and interface condensation heat transfer Nusselt number Nu Compared with experimental results, the error of the prediction is ranged within ±25%.