Abstract:

Based on the heat transfer analysis of two-phase zone augmentation technique employed in multiple parallel-pass (MPP) condenser, visualization and performance tests are employed to compare and evaluate the performance of MPP condenser by referencing a same-sized parallel flow(PF) condenser as a baseline sample.Visual observation by using a high-speed camera indicates that a more uniform refrigerant quality entering the next cooling pass can be achieved in MPP condenser because superheat vapor through a pass-through hole on flow distributor directly injects into a liquid -vapor zone in a header tube.In addition, analytical and test results show MPP condenser, being designed to enlarge two-phase condensing zone, is able to improve cooling performance as high as 9.6% while its refrigerant mass flow increases as high as 13.34% when comparing with a benchmark PF condenser.

Key words:

微孔管冷凝器, 传热性能, 可视化

摘要：

在分析混联式冷凝器中强化凝结传热机理的基础上，选用相同尺寸的平行流冷凝器为基准对比样件，通过高速摄影可视化实验及冷凝器性能测试方法， 对分流孔径为2.5、4.5 mm的两种混联式冷凝器进行可视化分析表明，类似于蒸气喷射流的过热蒸气与气液两相流在集流管中强烈扰动混合,改善了进入下一冷却流道的两相流质量分布的均匀性，扩展了两相流传热区域在混联式冷凝器中的相对占有面积，这使其传热性能比平行流冷凝器可提高9.6%; 同时，制冷系统中的制冷剂质量流量则提高13.43%，为设计更紧凑的空调冷凝器提供了一种新的途径。

关键词:

微孔管冷凝器, 传热性能, 可视化