低压闪蒸液滴温度与相变过程的研究

被引:24
作者
刘伟民 [1 ]
毕勤成 [1 ]
杨冬 [1 ]
董明晓 [2 ]
齐方成 [1 ]
毕新刚 [1 ]
机构
[1] 西安交通大学多相流动国家重点实验
[2] 西安交通大学机械工程学院
关键词
闪蒸; 低压; 液滴; 相变; 结冰;
D O I
10.16058/j.issn.1005-0930.2005.04.006
中图分类号
O414.1 [热力学];
学科分类号
080701 ;
摘要
在低压环境P=200—800Pa的工况范围内,研究了在闪蒸结冰过程中,液滴温度的变化与环境压力之间的关系.试验结果表明:在低压闪蒸结冰过程中,随着气压的降低,因为过热,液滴内部产生气泡的强度增加.液滴的破碎和液滴内部气泡的生长速度与环境压力有直接关系;在闪蒸过程中,液滴处于热力学非平衡状态,表现在液滴外侧发生的温度跳跃很小,而在液滴内部发生的温度跳跃很大;由于液滴蒸发的影响以及闪蒸过程中蒸发波的产生,即使在真空状态下,液滴周围仍存在一定的压力.
引用
收藏
页码:381 / 387
页数:7
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