微通道换热器两级均液竖直集管设计及两相分配特性  

Design and Two-Phase Distribution Characteristic of Two-Stage Distribution Vertical Header for Microchannel Heat Exchangers

作　　者：王晓宇 宋分平 谢李高 董超 赵日晶 黄东[1] Wang Xiaoyu;Song Fenping;Xie Ligao;Dong Chao;Zhao Rijing;Huang Dong(Department of Refrigeration&Cryogenic Engineering,Xi′an Jiaotong University,Xi′an,710049,China;Guangdong Midea Refrigeration Equipment Co.,Ltd.,Foshan,528311,China)

机构地区：[1]西安交通大学制冷与低温工程系,西安710049 [2]广东美的制冷设备有限公司,佛山528311

出　　处：《制冷学报》2024年第6期114-125,共12页Journal of Refrigeration

基　　金：国家自然科学基金(51876154)资助项目。

摘　　要：制冷剂两相分配均匀性是影响换热器性能的重要因素。针对微通道换热器采用竖直集管分液效果较差的问题,提出两级均液集管的设计方案,通过两相制冷剂分配测试,对比了不同干度和总流量下,各支路的气液相流量比率。实验结果表明:空集管的顶部支路缺液,底部过液,各支路液相流量的相对标准差(RSD)大于95%;多股流集管通过底部进液腔分配,在多股流通道中向上流动并从侧面出流孔进入环形横隔腔,各支路液相RSD大于60%;在多股流集管中加入芯部整流腔和顶部分配腔后,液相RSD在5%以内,气相RSD在15%以内,分配效果良好。The two-phase distribution uniformity of a refrigerant is an important factor affecting the heat exchanger performance.To address the poor uniformity of the liquid phase in the vertical header of the microchannel heat exchanger,a design scheme of a two-stage distribution header is proposed.The gas and liquid flow ratios of each branch under different dryness and total mass flow rates are compared by two-phase refrigerant distribution testing.The top branch of the empty header does not have a sufficient amount of liquid,while the bottom has excess liquid.The relative standard deviation(RSD)of the liquid phase for each branch is larger than 95%.The multiflow header uses the bottom inlet cavity to distribute the liquid,and then the liquid flows upward in the multiflow channel and enters the annular cavity through the side outlet hole.The liquid RSD of each branch is larger than 60%.When the core flow-regulated cavity and top distribution cavity are added into the multiflow header,the distribution performance is satisfactory,with RSDs of liquid and gas phases below 5%and 15%,respectively.

关 键 词：微通道换热器 竖直集管 制冷剂分配 两相 

分 类 号：TB657.2[一般工业技术—制冷工程] TB657.5