环形通道内再淹没过程流动传热现象实验研究

Experimental Study on Flow and Heat Transfer during Reflooding Process in a Vertical Annual Channel

通过可视化实验手段观察了环形通道内再淹没过程两相流动现象,分析总结了再淹没骤冷前沿推进过程中流型和传热机理的演化规律;通过不同工况下两相流动现象的对比,研究了是否加热和入口质量流速对再淹没过程流型和传热过程的影响规律。研究结果表明,在本参数范围内,实验中加热棒是否存在内释热对两相流动现象的影响不显著;而入口质量流速明显影响再淹没流动传热过程,入口质量流速越大,骤冷前沿附近汽化越剧烈,液膜中汽泡含量增加,更容易发生传热机制的转变。

Visual observations of the bottom reflooding process in an annular channel were carried out. From the visual study of the flow and heat transfer during reflooding phase, the flow regime and heat transfer mechanism transformations were studied. The comparison of phenomena during the reflooding under various conditions shows that the existence of the internal heat source in the heating rod has little effect on the characteristics of the flow and the heat transfer during the reflooding and that the inlet mass flow flux is a key factor that affects flow regimes and heat transfer characteristics. The greater the mass flux is, the easier the flow regime transition happens.