顾昕,文键,张星,王斯民,厉彦忠

• 1:西安交通大学能源与动力工程学院
• 2:西安交通大学化学工程与技术学院

摘要(Abstract)：

为了解新型环保工质R1234ze(E)微小通道内的冷凝换热及阻力特性,提出采用VOF(volumeoffluid)模型对R1234ze(E)和R134a(Tsat=40℃)在水平微细圆管(Dh=1 mm)内的冷凝过程进行数值模拟研究,探讨质量流量、干度以及物性对管内冷凝换热和阻力性能的影响。结果表明,R1234ze(E)和R134a的换热系数和压降都随质量流速和干度的增大而增大。相同情况下,R1234ze(E)换热系数小于R134a,但压降大于R134a。R1234ze(E)的液膜厚度平均要比R134a薄15.7%。当气液两相都为湍流,有效热导率对不同工质在水平圆管内的冷凝换热性能有重要影响。R1234ze(E)在管内的液膜分布特性整体上和R134a相似。现有的关联式对R1234ze(E)的压降都存在一定的低估,平均绝对误差都在30%左右。

关键词(KeyWords)： 微细通道;冷凝;R1234ze(E);换热系数;压降梯度

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金(51676146)

作者(Author): 顾昕,文键,张星,王斯民,厉彦忠

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