充液率对小型重力热管传热特性影响实验研究  

Role of Liquid Filling Ratio on Heat Transfer Characteristics in Miniaturized Gravitational Heat Pipe

作　　者：禹法文[1] 吉天成 刘向东[1,3] 张程宾 YU Fa-Wen;JI Tian-Cheng;LIU Xiang-Dong;ZHANG Cheng-Bin(Key Laboratory of Energy Thermal Conversion and Control of ministry of Education,School of Energy and Environment Southeast University,NanJing 210096,China;School of Energy and Environment Engineering,University of Science & Technology Beijing,Beijing 100083,China;School of Hydraulic,Energy and Power Engineering,Yangzhou University,Yangzhou 225127,China)

机构地区：[1]能源热转换及其过程测控教育部重点实验室,东南大学能源与环境学院,南京210096 [2]北京科技大学能源与环境工程学院,北京100083 [3]扬州大学水利与能源动力工程学院,扬州225127

出　　处：《工程热物理学报》2018年第12期2749-2754,共6页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.U1737104,No.51776037,No.51876184);江苏省自然科学基金资助项目(No.BK20170082).

摘　　要：开展了矩形槽道铝-乙醇小型重力热管的传热特性的实验研究,分析讨论了充液率对壁面温度分布、气液两相分布、热阻等热管传热性能的影响。研究表明,充液率对高热负荷工况的两相流动状态和传热特性有显著影响。两相脉动是高热负荷工况小型重力热管特有的两相流动现象.低充液率时,液塞易被气流冲破形成环状流,壁面温度几乎无波动。中等充液率时,在蒸汽和液塞的交替冲刷作用下,热管各段壁面温度均表现出脉动特性。高充液率时,液塞脉动速度的减小削弱了液塞对壁面的冲刷作用,壁面温度未出现明显波动.并且,中等充液率工况下气液两相的快速脉动增强了热管的传热性能,使得均温性和传热极限均优于低充液率和高充液率的情况.Heat transfer characteristics of a miniaturized aluminum-ethanol gravitational heat pipe with rectangular grooves were conducted experimentally,and the influence of filling ratio on wall temperature distribution,vapor-liquid two-phase distribution and thermal resistance were analyzed and discussed.The results indicate that the filling ratio play a significant role on the two-phase flow and heat transfer characteristics under high load condition.Oscillation state is the typical state of the miniaturized gravitational heat pipe under high heat load.For low filling ratio,the short liquid plug is broken easily by high velocity vapor to form the annular flow at the oscillation state, and no obvious fluctuation of wall temperature is observed.While for medium filling ratio,the wall temperature oscillation is caused by the alternative scour of the vapor and liquid plug in each sections.For high filling ratio,with decreasing oscillation velocity of liquid plug,the weaken scour of liquid plug on the wall has not caused obvious wall temperature fluctuation.At the condition of medium filling ratio,the rapid oscillation of vapor and liquid strengthen the heat transfer,and hence the temperature uniformity and heat transfer limit are better than those of the low and high filling ratio.

关 键 词：重力热管 传热 充液率 脉动 

分 类 号：TK124[动力工程及工程热物理—工程热物理]