Abstract Heat transfer performance of downward-facing flat heaters is summarized in this paper. The combined effects of material, orientation, dimension and pressure are considered. According to the overall trends, the results show complicated tendencies in which the parameters are interrelated. With the heat transfer characteristics, some CHF trends that have been observed in previous studies are analyzed. Some transitional phenomena occur with orientation, and a related analysis is conducted using a dry-spot concept. Various environments like pressurized conditions are considered in this study, including real accidental conditions. For the material effect, a real material, carbon steel, used for the severe accident mitigation strategies is considered. The overall heat transfer performance at the most critical locations of the severe accident strategies can be extracted from the results.

中文翻译：

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面向下的碳钢和不锈钢表面的传热性能

摘要 本文总结了下向平面加热器的传热性能。考虑了材料、方向、尺寸和压力的综合影响。根据总体趋势，结果显示出参数相互关联的复杂趋势。通过传热特性，分析了之前研究中观察到的一些 CHF 趋势。一些过渡现象随方向发生，使用干点概念进行相关分析。本研究考虑了各种环境，如加压条件，包括真实的意外条件。对于材料效应，考虑了用于严重事故缓解策略的真实材料碳钢。