Abstract The application of microchannel heat exchanger (MCHX) technology for the development of compact, high power density integral steam generators is investigated. A representative MCHX test section with two-phase flow of water on one side and hotter, single-phase flow of water on the other side is designed and fabricated. A test facility with hot, boiling, and cold fluid loops, respectively, is developed to experimentally investigate the heat duty and pressure drop performance of the MCHX steam generator under a wide range of operating conditions. Tests designed to isolate specific heat transfer regimes such as subcooled boiling, saturated boiling and dryout are conducted to assess the accuracy of correlations and transition criteria available in the literature. The 0.248 × 0.056 × 0.041 m MCHX steam generator transferred ~65 kW for the conditions investigated. A segmented heat transfer and pressure drop model is developed for the MCHX steam generator using the closure models that provide the best agreement with the data from the regime-specific experiments. The resulting model provides good agreement with the overall data set, with an Absolute Average Deviation (AAD) of ~3% and ~10% for heat duty and pressure drop, respectively, for the data points for which the exit is predicted to be in the saturated boiling flow regime. For the data points where the exit flow is predicted to be in the post-dryout regime, the AADs for heat duty and pressure drop are ~12.4% and ~5.6%, respectively. The experimentally validated model developed in this study could aid the design and development of modular, MCHX steam generators for both large-scale as well as small modular reactors.

中文翻译：

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用于整体蒸汽发生器应用的微通道换热器中流动沸腾的实验研究和建模

摘要 研究了微通道换热器 (MCHX) 技术在开发紧凑型、高功率密度整体蒸汽发生器中的应用。设计并制造了一个具有代表性的 MCHX 测试段，一侧具有两相水流，另一侧具有较热的单相水流。分别开发了具有热、沸腾和冷流体回路的测试设备，以实验研究 MCHX 蒸汽发生器在各种操作条件下的热负荷和压降性能。进行旨在隔离特定传热状态（例如过冷沸腾、饱和沸腾和干燥）的测试，以评估文献中可用的相关性和转变标准的准确性。0.248 × 0.056 × 0。041 m MCHX 蒸汽发生器在所研究的条件下传输约 65 kW。使用闭合模型为 MCHX 蒸汽发生器开发了分段传热和压降模型，该模型提供与特定制度实验数据的最佳一致性。所得模型与整体数据集具有良好的一致性，对于预测出口所在的数据点，热负荷和压降的绝对平均偏差 (AAD) 分别为 ~3% 和 ~10%。饱和沸腾流态。对于出口流量预计处于干燥后状态的数据点，热负荷和压降的 AAD 分别为 ~12.4% 和 ~5.6%。本研究中开发的经过实验验证的模型可以帮助设计和开发模块化、