水平微细圆柱表面与水自然对流换热的实验研究  

Experimental study on heat transfer of natural convection between horizontal micro-wire and water

作　　者：董庆[1] 孙立[2] 贺建昆[1] 

机构地区：[1]山东理工大学轻工与农业工程学院,山东淄博255049 [2]山东省科学院能源研究所,山东济南250014

出　　处：《山东理工大学学报（自然科学版）》2007年第5期85-87,共3页Journal of Shandong University of Technology:Natural Science Edition

摘　　要：采用焦耳加热法对不同尺寸的水平微细铜丝在水中加热,并将实验得到的努谢尔特数Nu与常规尺寸下经典准则关系式的计算值比较.实验结果表明,在相同壁面过热度下,实验Nu数要小于经典准则关系式的计算值,并且实验Nu数几乎保持不变.这说明微细铜丝与水的换热由对流为主转变为对流与导热共同作用为主或是纯导热,从而导致了实验值小于常规尺寸下的理论计算值.The heat transfer of the natural convection of horizontal micro-wire with different outer diameters is experimentally investigated by using the Joule heating. Water is used as the working fluid. The experimental Nusselt number is compared with that of the classical correlations. The ex- perimental results show that the experimental data are less than the correlations values and the experimental data are almost constant. It is the predomination from natural convection to the conjunct effect of natural convection and conduction that results in the phenomenon.

关 键 词：焦耳加热 微细铜丝 自然对流换热 努谢尔特数 

分 类 号：TK124[动力工程及工程热物理—工程热物理]