Investigation on condensation heat transfer and pressure drop of R410A during upward flow in vertical smooth and micro-fin tube
Investigation on condensation heat transfer and pressure drop of R410A during upward flow in vertical smooth and micro-fin tube
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DOI：
10.1016/j.ijheatmasstransfer.2017.01.053
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发表时间：
2017-05
影响因子：
5.2
通讯作者：
Yunxiao Yang;L. Jia;Qi Peng
中科院分区：
文献类型：
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作者：
Yunxiao Yang;L. Jia;Qi Peng
对内径为8.32 mm的光滑管和翅片根部直径为8.76 mm的微翅片管内蒸汽向上流动时R410A制冷剂冷凝时的传热和压降性能进行了实验研究。测试段为0.5 m长的双管，制冷剂在内管中流动，冷却水在环空中以相同方向流动。实验在饱和温度 40°C、45°C 和 48°C 下进行，质量通量在 80–345 kg/m2s 范围内。试验段设置了四种不同的冷却水流量工况，比较了光滑管和微翅片管的传热强化因子和压降惩罚因子。测试部分的总压降由差压传感器直接测量。实验数据与一些众所周知的微翅片管传热关系式进行了比较。 Chamra 和 Mago 提出的相关性与当前数据最为吻合，平均偏差为 31.08，平均偏差为 35.74。基于实验数据，提出了微翅片管中冷凝传热和摩擦压降的两个修正关系式，分别在±15%和±25%偏差范围内。
Heat transfer and pressure drop performance of refrigerant R410A condensation during vapor flowing upward in a smooth tube with inner diameter of 8.32 mm and a micro-fin tube with fin root diameter of 8.76 mm are experimentally investigated. The test section is a 0.5 m long double tube with refrigerant flowing in the inner tube and cooling water flowing in the annulus in the same direction. Experiments are conducted at saturation temperatures 40 °C, 45 °C and 48 °C with mass fluxes in the range of 80–345 kg/m2s. Four different cooling water flow conditions in the test section are set up to compare the heat transfer enhancement factors and pressure drop penalty factors of the smooth tube and micro-fin tube. The total pressure drops across the test section are directly measured by a differential pressure transducer. The experimental data are compared with some well-known heat transfer correlations of micro-fin tube. The correlation suggested by Chamra and Mago shows the best agreement with the present data and exhibits an average deviation of 31.08 and a mean deviation of 35.74. Based on the experimental data, two revised correlations for condensation heat transfer and the frictional pressure drop in micro-fin tube are proposed, within ±15% and ±25% deviation band respectively.