| 摘要: |
| 实验研究了R290、R22在细圆管中的流动凝结换热特性。实验管内径为1.085 mm，R22的质量流率为200~1200 kg/(m2?s)，R290的质量流率为200~650 kg/(m2?s)，饱和温度分别为40 ℃与50 ℃。实验结果表明，高质量流率时R22在较高干度下换热系数随干度增加缓慢或略有下降，低质量流率时，R290在较小干度下出现换热系数下降。两种制冷剂蒸气相比，相同条件下R290的凝结换热系数高于R22的。本文的实验结果还与现有典型关联式的计算结果作了对比，其中，Wang et al.(2002)关联式对R290的实验数据预测偏差在17.5%之内，Kim et al. (2013)关联式对R22的实验数据预测偏差在18.4%之内。 |
| 关键词: 微细通道 流动凝结 对流换热 R290 |
| DOI： |
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| 基金项目:国家自然科学基金创新研究群体项目 (51321002）、环境保护部环境保护对外合作项目和国家科技支撑计划项目（2012BAA13B02）资助。 |
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| Experimental Study on the Flow Condensation Heat Transfer of R290 and R22 in a Horizontal Circular Minitube |
| Xiao Hang,Li Junming |
| (Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering , Tsinghua University) |
| Abstract: |
| The condensation heat transfer characteristics of R290 and R22 were investigated experimentally in a horizontal circular minitube with 1.085 mm diameter. The mass flow rate of R22 is 200-1200 kg/(m2?s), and that of R290 is 200-650 kg/(m2?s). The saturation temperature is 40 ℃ and 50 ℃ respectively during the experiment. The experimental results show that at the higher mass flow rate of R22, the condensation heat transfer coefficient increases slowly or even decreases little with the vapor quality increasing, for the R290 at a less mass flow rate, the heat transfer coefficient will decreases slightly at a low vapor quality. The condensation heat transfer coefficient of R290 is higher than that of the R22 at the same experimental conditions. The experimental results are also compared with some of the existing correlations, which shows that the Wang et al.(2002) correlation predicts the experimental data of R290 very well ,with an overall mean absolute error of 17.5%, while Kim et al. (2013) correlation makes the best prediction to the R22’s data, with an overall mean absolute error of 18.4%. |
| Key words: minichannel flow condensation convective heat transfer R290 |
