层流区CuO-水纳米流体流动与对流换热特性(英文)  

Heat Transfer Properties of CuO-water Nanofluids in Laminar Flow

作　　者：张邵波[1] 骆仲泱 寿春晖[1] 倪明江[1] 岑可法[1] 

机构地区：[1]能源清洁利用国家重点实验室(浙江大学),浙江省杭州市310027

出　　处：《中国电机工程学报》2009年第32期58-65,共8页Proceedings of the CSEE

基　　金：Supported by National Natural Science Foundation of China(50676082)~~

摘　　要：测量了3种不同粒径(23、51和76nm)的CuO-水纳米流体在层流状态下的管流对流换热系数,对比不同纳米颗粒粒径对层流区对流换热的影响。实验结果表明,在液体中添加纳米粒子增大了液体的管内对流换热系数,且在相同雷诺数条件下,23nm粒径的纳米流体对流换热系数要比其他2种粒径的纳米流体对流换热系数高出大约10%。基于有效介质理论和分型理论,得出新的纳米流体有效导热系数关联式,使用此关联式计算对流换热系数能够得到更加精确的实验方程。The laminar convective heat transfer behavior of CuO nanoparticle dispersions in water with three different particle sizes （23, 51, and 76 nm） was investigated experimentally in a flow loop with constant heat flux. The main purpose of this study is to evaluate the effect of particle size on convective heat transfer in laminar region. The experimental results show that the suspended nanoparticles remarkably increase the convective heat transfer coefficient of the base fluid, and the nanofluid with 23 nm particles shows higher heat transfer coefficient than nanofluids containing the other two particle sizes about 10% under the same Re. Based on the effective medium approximation and the fractal theory, the effective thermal conductivity of suspension was obtained. It is shown that if the new effective thermal conductivity correlation of the nanofluids is used in calculating the Prandtl （Pr） and Nusselt number （Nu）, the new correlation accurately reproduce the convective heat transfer behavior in tubes.

关 键 词：纳米流体 对流换热系数 层流 黏度 

分 类 号：TK124[动力工程及工程热物理—工程热物理]