两相流板翅式换热器入口分配特性的实验研究

实验研究了板翅式换热器入口两相流分配不均匀性问题．结果表明：两相流在换热器入口截面上的分配不均匀主要体现在液相上，其中又以横向不均匀为主；气体雷诺数及干度对两相流的分配特性有很大的影响；对于整个横截面上的二维分布情况，气相与液相的分配不均匀度均随着气体雷诺数的增大而增大，液相的不均匀度随着干度的增大而增大，气相的不均匀度随着千度的增大而减小；气体雷诺数的变化主要影响液相在横向上的分配特性，干度的变化主要影响液相在纵向上的分配特性．

Experimental Study on Two-Phase Flow Maldistribution at the Entrance of Plate-Fin Heat Exchangers

Two-phase flow distribution in the entrance of plate-fin heat exchangers was experimentally studied. It is found that gas Re and dryness are the main factors affecting two-phase flow distribution. A parameter of dimensionless velocity deviation is defined to describe maldistribution in two orthogonal directions. The results indicate that the liquid flow nonuniformity is more apparent than that of gas and the flow maldistribution in crosswise direction is more violent than that in the ordinate direction. The flow maldistribution of both gas and liquid components increase with the increase of gas flow Re. The gas flow maldistribution decreases with the inlet dryness increasing, but the liquid flow maldistribution increases simultaneously. It is also found that the liquid flow profile in the crosswise direction is strongly affected by the variation of gas flow Re and that in ordinate direction is mainly affected by the two-phase flow dryness.