微重力池沸腾现象中的临界热流密度  

CHF OF NUCLEATE POOL BOILING IN MICROGRAVITY

作　　者：刘刚[1] 赵建福[1] 万士昕[1] 闫娜[1] 

机构地区：[1]中国科学院力学研究所国家微重力实验室,北京100080

出　　处：《工程热物理学报》2007年第z2期13-16,共4页Journal of Engineering Thermophysics

基　　金：中国科学院知识创新工程(No.KJCX2-SW-L05);国家自然科学基金(No.10432060)

摘　　要：本文利用我国第22颗返回式卫星实验研究了微重力条件下池沸腾临界热流现象,发现基于流体动力学不稳定性机制的LD-Zuber模型可以很好地预测不同重力条件下的池沸腾临界热流变化趋势,尽管热丝无量纲半径比该模型的适用范围扩大了3～4个数量级。这和地面常重力环境中关于临界热流尺度效应的研究结果有很大差异,表明在Bond数很小时,热丝无量纲半径已不再是描述临界热流尺度效应的唯一参数。此外,本文提出了"极限核化尺寸"的概念,来解释了不同条件下临界热流的变化特征。In the present paper,the phenomenon of critical heat flux(CHF)of pool boiling in microgravity are studied experimentally aboard the 22nd Chinese recoverable satellite.It has been found that the trend of CHF in different gravity conditions can be predicted well by the LD-Zuber model based on the mechanism of hydrodynamic instability,although the range of the dimensionless radius is extended by 3～4 decades above the originally set limit.It's utterly different from the results in normal gravity.Thus,it must be concluded that the dimensionless radius is not able to describe adequately the scaling of CHF in the cases of small Bond number.A new concept,namely the critical nucleate size,is proposed to explain the difference of CHF in different conditions.

关 键 词：微重力 池沸腾 CHF 尺度效应 极限核化尺寸 

分 类 号：TK124[动力工程及工程热物理—工程热物理]