高饱和蒸发压力氨喷雾冷却沸腾传热特性  

Boiling heat transfer characteristics under high saturated vapor pressure on spray cooling with ammonia

作　　者：余勇胜[1] 王宏[1,2] 朱恂[1,2] 廖强[1,2] 丁玉栋[1,2] 杨宝海[1] 

机构地区：[1]重庆大学工程热物理研究所,重庆400030 [2]重庆大学低品位能源利用及系统教育部重点实验室,重庆400030

出　　处：《热科学与技术》2011年第1期32-37,共6页Journal of Thermal Science and Technology

基　　金：国家自然科学基金资助项目(50906102);"211工程"三期建设资助项目(S-09101);教育部留学回国人员科研启动基金资助项目(教外司留[2010]1561号)

摘　　要：利用冷却工质的相变蒸发带走大量热量的喷雾相变冷却技术成为大功率电子元件散热需求的最佳途径。建立了双喷嘴阵列氨喷雾相变冷却实验系统,研究了饱和蒸发压力以及进口流量对氨喷雾相变冷却传热特性的影响规律。实验结果表明:在氨喷雾相变冷却过程中,维持较高的饱和蒸发压力有利于传热系数提高,过热度降低;流量对传热特性影响较大,低流量时,强迫对流传热向核态沸腾传热的转换更明显;在相同流量下,当饱和蒸发压力为403 kPa时,传热系数最大可达145 323 W/(m2.K),是饱和蒸发压力在117 kPa下的传热系数的51%。Spray cooling technique,which can remove a large amount of heat by evaporation of working fluid,is considered as a promising cooling technology for high-power electronic components.In the present study,an spray cooling system with two pressure atomizing nozzles using ammonia as working fluid was set up to investigate the effects of saturated vapor pressure and inlet flow rate on heat transfer characteristics of the heating surface.The experimental results showed that the heat transfer coefficient was enhanced while superheat was reduced when a high saturated vapor pressure was applied in the cooling system.Meanwhile,the heat transfer process was significantly influenced by inlet working fluid flux,and a noticeable transition from forced convection heat transfer to nucleate boiling heat transfer was observed under lower flow rate.For the cases with average flow rate of 4.256 g/s,the heat transfer coefficient reached the maximum value of 145 323（W/（m2·K））when the saturated vapor pressure was 403 kPa,which was 51% higher than that obtained under the saturated vapor pressure of 117 kPa.

关 键 词：喷雾冷却 液氨 流量 饱和压力 高热流密度 

分 类 号：TK124[动力工程及工程热物理—工程热物理]