多元平行流冷凝器流程布置的模拟研究与分析

摘要

A steady-state general-purpose mathematic model of distributed parameter for multi-unit parallel-flow type condenser was derived according to the characteristics of it. The simulation and analysis of the heat transfer and the flow characteristics in parallel-flow type condenser of different pass number were carried out. It is found the law that increasing the pass number has an effect on heat transfer and refrigerant side pressure drop, and get the conclusion that to ensure the condenser has appropriate pressure drop, not make pass numbers too many. And the effect of many kinds of flow tube number arrangement on multi-unit parallel-flow condenser was studied.The results show that the distribution cases of row numbers for each pass flat-tube have less influence on heat transfer of condenser, and mainly impact the changes of in refrigerant side pressure drop. Two-phase section should serve condenser as a core theme of body parts to ensure that the entire condenser has a higher performancance of heat transfer. Becanse of the subcooling section's great in on pressure drop,the tube numbers in subcooling shouldn't be too few.%根据多元平行流冷凝器的特点,采用分布参数法对其建立了稳态数学模型.对不同流程数的多元平行流冷凝器的传热和流动性能进行了模拟计算和分析比较,发现了增加流程数对换热量和制冷剂侧压降影响的规律;得出了为保证冷凝器合适的压降,不宜使整体流程数过多的结论.同时,对多元平行流冷凝器的多种各流程扁管排数分配方式进行了模拟比较.结果表明:各种各流程扁管排数分配方式对冷凝器的换热量影响相对较小,主要影响制冷剂侧压降的变化;两相段应该作为冷凝器芯体的主体部分,以保证整个冷凝器有较高的换热性能;由于过冷段扁管排数对制冷剂侧压降影响较大,不宜过少.