Abstract In order to investigate heat transfer characteristics of steam/nitrogen condensation inside horizontal enhanced condensation channels (HECCs), experiments have been performed, respectively, inside HECC and horizontal circular channel (HCC). HECC is formed by inserting different reinforcers into HCC including horizontal multi-start straight channels (HMSSCs) and horizontal spiral channels (HSCs). Effects of nitrogen mass fractions on average condensation heat transfer coefficients (CHTCs), average outlet condensate mass flowrates (CMFRs), and average steam-side pressure drops (SSPDs) are analyzed, respectively. The results indicate that HECC has better condensation performance than HCC under the same conditions, while average SSPDs of HECC will increase slightly. Then, HMSSC is compared against HCC, and enhancement factors of average CHTCs and average outlet CMFRs are about 1.45 and 1.12, respectively, while the enlargement factor of average SSPDs is about 1.16. Similarly, HSC is compared against HCC, and enhancement factors of average CHTCs and average outlet CMFRs are about 1.25 and 1.05, respectively, while the enlargement factor of average SSPDs is about 1.12.

中文翻译：

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水平强化冷凝通道内蒸汽/氮气冷凝特性的实验研究

摘要 为了研究水平增强冷凝通道（HECC）内蒸汽/氮气冷凝的传热特性，分别在HECC和水平圆形通道（HCC）内进行了实验。HECC 是通过在 HCC 中插入不同的增强剂而形成的，包括水平多起点直通道 (HMSSC) 和水平螺旋通道 (HSC)。分别分析了氮质量分数对平均冷凝传热系数 (CHTC)、平均出口冷凝质量流量 (CMFR) 和平均蒸汽侧压降 (SSPD) 的影响。结果表明，在相同条件下，HECC 的冷凝性能优于 HCC，而 HECC 的平均 SSPDs 会略有增加。然后，将 HMSSC 与 HCC 进行比较，平均CHTCs和平均出口CMFRs的增强因子分别约为1.45和1.12，而平均SSPDs的放大因子约为1.16。同样，HSC 与 HCC 进行比较，平均 CHTCs 和平均出口 CMFRs 的增强因子分别约为 1.25 和 1.05，而平均 SSPDs 的放大因子约为 1.12。