| 摘要: |
| 比较了CAVALLINI的纯质和混合工质水平内螺纹管中流动沸腾换热系数的关联式,结果显示在内螺纹管中,对近共沸混合工质R404A的沸腾换热系数进行工程计算时,R404A被看作纯质和混合工质计算所得的沸腾换热系数值差别最大不到10%,因此可将其以纯质对待;对CAVALLINI的纯质和混合工质、KOYAMA及THOME等四个水平内螺纹管流动沸腾换热系数的影响因素进行对比分析,结果表明R404A的沸腾换热中对流沸腾换热占主导地位,且随干度增加而增加.对关联式的理论预测和实验结果进行对比,表明CAVALLINI和THOME关联式的预测误差小于21%,因此它们对R404A适用性较好,这对R404A蒸发器的工程设计及优化具有一定参考意义. |
| 关键词: 工程热物理 近共沸工质 沸腾换热系数 内螺纹管 |
| DOI： |
| 修订日期：2004-02-19
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| 基金项目: |
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| Ivestigation on Flow Boiling Heat Transfer Characteristics of R404A in Horizontal Microfin Tube |
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| Abstract: |
| Considering R404A as a pure and mixed refrigerant respectively, the boiling heat transfer coefficients were calculated inside horizontal 9.52 mm o.d. microfin tube. The difference of less than 10% between the two calculations shows that R404A can be taken as pure fluid in practical calculation. Cavallini, Koyama and Thome correlations for boiling heat transfer inside microfin tube all indicate that the convective heat transfer plays a predominant role in total boiling heat transfer. The predicted values by the above correlations were compared with the experimental data. The result shows that Cavallini and Thome correlations can well predict the boiling heat transfer of azeotropic mixture R404A with the error of less than 21%. |
| Key words: R404A |
