扭曲方管传热性能的数值模拟分析  

Numerical Study of Heat Transfer Performance in Twisted Square Duct

作　　者：于菲菲[1] 王良璧[1] 

机构地区：[1]兰州交通大学机电工程学院,甘肃兰州730070

出　　处：《兰州交通大学学报》2010年第3期49-54,共6页Journal of Lanzhou Jiaotong University

基　　金：国家自然科学基金(50876040)

摘　　要：运用数值分析的方法,对层流条件下等壁温的扭曲方管的传热性能进行研究,并与直方管的结果进行对比.主要针对Re=300-1600,扭率Tr=5-20这一过程的扭曲方管的传热性能进行了分析.计算结果表明：在相同的Tr下,管内空气通道的Nu随着Re的增大而增加,摩擦因子f随着Re的增大而减小;在相同的Re下,管内空气通道的Nu和f随着Tr的增大而减小,Re越大,减小的趋势越明显.扭曲方管在不同Tr的情况下均有强化传热指标η〉1,从而说明由于二次流的存在,扭曲方管具有强化传热效果.This paper is devoted to a numerical study of heat transfer performance of laminar twisted square duct under the condition of uniform temperature of walls and the results obtained are compared with those of a straight untwisted square duct.The heat transfer performance of twisted square duct is at Re from 300 to 1600 and Tr between 5 and 20.The results indicate that at the same Tr,when Re increases,Nu increases while the friction factor f decreases;at the same Re,Nu and f decrease when Tr increases.The larger Re is,the greater the decrease of Nu and f are.The heat transfer enhancement factor η of twisted duct is always greater than 1 no matter how Tr may change.The results affirm that the twisted square duct can enhance laminar convective heat transfer due to the existing of secondary flow.

关 键 词：二次流 强化传热 扭曲方管 

分 类 号：TK124[动力工程及工程热物理—工程热物理]