Abstract

Aiming at studying the condensate flow phenomenon and air-steam–mixture condensation heat transfer underneath a containment vessel surface, a test bench was constructed. The plate dimension was 1.5 × 0.6 m, with Carbozinc 11 coating on the surface, suspended in a pressure vessel with 2.5-m diameter and 4.5-m height. The air-steam mixture was condensed on an inclined plate through natural convection mode and jet mode. By observing flow behavior on the plate through a viewport, four basic regimes were obtained as the inclination angle gradually increased: droplet, droplet to rivulet transition, developed rivulet, and uniform film. During the experiment, we observed a steam atomization phenomenon; therefore, the model predicted better with the atomization effect considered. A simple formula from the condensation data is proposed when the air mole fraction is small. The error between the experimental results and the predicted data is within 25%.

摘要

为研究安全壳表面下方的凝结水流动现象和空气-蒸汽-混合物凝结传热，搭建了试验台。板尺寸为 1.5 × 0.6 m，表面有 Carbozinc 11 涂层，悬浮在直径为 2.5 米、高度为 4.5 米的压力容器中。空气-蒸汽混合物通过自然对流模式和喷射模式在斜板上冷凝。通过观察窗观察板上的流动行为，随着倾斜角逐渐增加，获得了四种基本状态：液滴、液滴到小溪的过渡、发展的小溪和均匀的薄膜。在实验过程中，我们观察到了蒸汽雾化现象；因此，该模型在考虑雾化效应的情况下预测得更好。当空气摩尔分数很小时，根据冷凝数据提出了一个简单的公式。实验结果与预测数据的误差在25%以内。