水轮机HFC-4310蒸发冷却换热特性及相关性研究  

Research on the Heat Transfer Characteristic and Correlations of HFC-4310 Evaporative Cooling in Hydrogenerators

作　　者：秦光宇 赵艳伟[4] 王雄师[4] 李广德 吕俊复 吴玉新 QIN Guangyu;ZHAO Yanwei;WANG Xiongshi;LI Guangde;LV Junfu;WU Yuxin(State Key Laboratory of Hydro-Power Equipment,Harbin 150040,China;Harbin Electric Machinery Company Limited,Harbin 150040,China;Harbin Research Institute of Large Electric Machinery Co.,Ltd.,Harbin 150040,China;Key Laboratory for Thermal Science and Power Engineering of Ministry of Education(Tsinghua University),Beijing 100084,China)

机构地区：[1]水力发电设备国家重点实验室,哈尔滨150000 [2]哈尔滨电机厂有限责任公司,哈尔滨150000 [3]哈尔滨大电机研究所有限公司,哈尔滨150000 [4]清华大学热科学与动力工程教育部重点实验室(清华大学),北京100084

出　　处：《大电机技术》2025年第2期62-69,77,共9页Large Electric Machine and Hydraulic Turbine

基　　金：水力发电设备国家重点实验室开放课题(SKLHE-ORF-202105)。

摘　　要：蒸发冷却技术因其冷却效能高,在水轮发电机定子线棒冷却中具有广阔的应用前景,准确预测蒸发冷却管内传热特性对于水轮发电机的安全运行至关重要。本文旨在建立以十氟戊烷(HFC-4310)为工质的蒸发冷却管内的流动换热计算方法,根据不同尺寸选型的矩形空心导线在5000A~7500A负荷下的沿程温度分布数据,对比分析了三种单相流动换热(Kays-Crawford、Whitaker、Dittus-Boelter)关联式和四种饱和沸腾换热(Chen、Gungor-Winterton、Lazarek-Black、Li-Wu)关联式的准确性。误差分析结果表明,单相流动换热中Dittues-Boelter关联性能更准确地计算单相段沿程温度分布,饱和沸腾换热中Li-Wu关联式准确性最高,平均相对误差在5%以内。采用过冷沸腾的传热模型可有效提升预测精度,据此分析了5种矩形空心导线的实心管温度分布分析其散热性能,结果表明,在相同电流强度下,2.5×9.5的矩形空心导线冷却性能最佳。Evaporative cooling technology has broad application prospects in stator rod cooling of hydro-generator due to its high cooling efficiency.Accurate predictions of heat transfer characteristics in evaporative cooling tube is of great importance for safe operation of hydro-generator.The purpose of this paper is to establish a model of heat transfer for evaporative cooling tubes with HFC-4310 as the work medium.The accuracy of three single-phase forced convection heat transfer correlations and four saturation boiling heat transfer correlations have been evaluated based on the temperature distributions of rectangular hollow conductors under loads of 5000A~7500A.The results demonstrated that the Dittues-Boelter correlation can get more accurate temperature distribution along single-phase section.And the Li-Wu correlation had the highest accuracy with an average relative error within 5%.The correlation with the subcooled boiling model can achieve the best prediction performance.The temperature distribution of five rectangular hollow conductor selections was evaluated based on the above correlations.And the results showed that the rectangular hollow conductor of 2.5×9.5 has the best cooling performance under the same current intensity.

关 键 词：蒸发冷却 十氟戊烷 饱和沸腾换热 单相强制对流换热 

分 类 号：TK733[交通运输工程—轮机工程]