高雷诺数条件下超临界压力CO2在垂直圆管内换热特性的实验研究  

Experimental Investigation of Conevection Heat Transfer of CO_2 at Supercritical Pressures in a Vertical Circular Tube at High Re

作　　者：李志辉[1] 姜培学[1] 

机构地区：[1]清华大学热能工程系,热科学与动力工程系教育部重点实验室,北京100084

出　　处：《核动力工程》2008年第6期41-45,共5页Nuclear Power Engineering

基　　金：教育部科学技术重大项目(306001);国家863计划项目(2006AA05Z416)

摘　　要：对超临界压力CO2在高雷诺数条件下的垂直圆管(d=2 mm)内向上流动时的换热特性进行了实验研究,分析了热流密度、质量流量、进口温度、压力、浮升力和热加速等因素对壁温和换热的影响。实验结果表明:热流密度比较高的情况下,向上流动时会出现局部换热恶化现象;质量流量的提高会消除或推迟换热恶化的发生;不同的进口温度对换热能力有很大的影响;压力的提高会降低换热恶化的程度。Convection heat transfer during the upward flow of CO2 at supercritical pressures in a vertical circular tube （dim=2 mm） at high Reynolds numbers was investigated experimentally, and the effects of heat fluxes, mass fluxes, inlet temperatures, pressures, buoyancy and thermal acceleration on the convection heat transfer was analyzed. The results show that the tube wall temperature occurs abnormally distribution for high heat-fluxes with upward flow. The degree of deteriorated heat transfer increases with increasing heat flux. Increasing of the mass flux delays the occurrence of the deterioration of heat transfer and weakens the deterioration of heat transfer down-stream section. The inlet temperature strongly influences the heat transfer. The deterioration degree of heat transfer decreases with increasing pressure.

关 键 词：超临界压力CO2 质量流量 热流密度 压力 

分 类 号：TK124[动力工程及工程热物理—工程热物理]