多孔扁管内单相对流换热特性的实验研究  

Experimental Investigation on Convective Heat Transfer of Liquid Flow in Multi-Port Extruded Tubes

作　　者：代宝民[1] 李敏霞[1] 党超镔[2] 马一太[1] 陈启 

机构地区：[1]天津大学机械工程学院中低温热能高效利用教育部重点实验室,天津300072 [2]日本东京大学 [3]天津三电汽车空调有限公司,天津300385

出　　处：《工程热物理学报》2015年第4期843-846,共4页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.51176133);天津市科技计划项目(No.12JCYBJC13800)

摘　　要：对水力直径为0.715 mm的方孔及0.86 mm的圆孔多孔扁管内液相流体对流换热特性进行了实验研究,Re数范围为50~2300,入口温度为5~45℃,加热热流密度为3~9 kW/m^2。实验结果表明,对流换热在Re=2000附近发生过渡;入口段效应明显;在Re数较小时,Nu数明显小于充分发展流动的预测值;热流密度越大、入口温度越高,对流换热强度越低。两种管型扁管的实验值变化趋势一致,但圆孔Nu数高于方孔。基于尺度效应的影响及经典层流换热理论对实验结果进行了修正。An experiment was conducted to study the convective heat transfer characteristics of liquid flow through two multi-port extruded tubes.The hydraulic diameters are 0.715 and 0.86 mm with the cross section of rectangular and circular,respectively.The experiment was performed with the Reynolds number(Re) in the range of 50~2300,inlet temperature of 5~45℃,and heat flux of3~9 kW/m^2.The experiment shows that the heat transfer transits at Re of about 2000;the influence of entrance effect is predominant;the Nusselt number(Nu) is significantly lower than the prediction value of fully developed flow at low Re;the heat transfer performance decreases with the increase of heat flux and inlet temperature.Additionally,the experimental variation trends are in agreement with each other for the two tubes despite of different geometries,but Nu of the circular tube is much higher.Finally,the experimental results were corrected considering the scaling effects and classical laminar heat transfer theories.

关 键 词：多孔扁管 微通道 对流传热 单相 尺度效应 

分 类 号：TK124[动力工程及工程热物理—工程热物理]