核化点间距对过冷沸腾中汽泡聚并特性的影响

Effects of Nucleation Site Spacing on Bubble Merger Characteristics during Subcooled Boiling

过冷沸腾是反应堆热工过程中会出现的重要物理现象,汽泡聚并是核态沸腾过程中一种常见的汽泡相互作用形式。本文对核态沸腾过程中的汽泡聚并现象做了研究,研究了不同核化点间距下汽泡聚并特性和热流密度特征。利用微型加热片阵列,控制核化点的间距,并且详细记录汽泡底部的热流密度,与此同时用高速CCD相机从底部拍摄汽泡运动形态。将汽泡图像与热流密度结合分析,全面总结核化点间距对汽泡聚并和热流密度特性的影响。

Subcooled boiling is an important phenomenon during the thermal hydraulics process in nuclear reactors. Bubble merger is a common form of bubble interactions. This paper studies bubble merger characteristics and heat flux distributions at various nucleation site spacing. A microheater array is used to control the nucleation site spacing and measure the heat fluxes in detail. A CCD camera measures the bubble dynamics from bottom view. The correlations of bubble dynamics and heat flux distributions under bubbles are analyzed and the effects of nucleation site spacing are summarized.