作　　者： ; ;

机构地区： 华南理工大学化学与化工学院传热强化与过程节能教育部重点实验室

出　　处： 《化工学报》 2009年第8期1944-1949,共6页

摘　　要： The distributions of thermal resistance in viscous sublayer,buffer region and turbulent core region,local flow resistance and local heat transfer characteristics at different locations downstream of the twisted-tape element were numerically studied in a converging-diverging tube inserted with spaced twisted-tape element by analyzing the attenuation of self-sustaining swirl flow.The results showed that the local performance was poor as thermal resistance was too concentrated in its distribution for a particular region.The more uniform the distribution of thermal resistance,the better the local performance.The local performance reached its best when the fluid just left the spaced twisted-tape,in which the flow resistance dropped substantially but the enhancement of heat transfer was still significant.The self-sustaining flow was maintained at a long distance.The best performance was at the length of 36.85 times the diameter,increasing by 6.8% compared with a converging-diverging tube. The distributions of thermal resistance in viscous sublayer, buffer region and turbulent core region, local flow resistance and local heat transfer characteristics at different locations downstream of the twisted-tape element were numerically studied in a converging-diverging tube inserted with spaced twistedtape element by analyzing the attenuation of self-sustaining swirl flow. The results showed that the local performance was poor as thermal resistance was too concentrated in its distribution for a particular region. The more uniform the distribution of thermal resistance, the better the local performance. The local performance reached its best when the fluid just left the spaced twisted-tape, in which the flow resistance dropped substantially but the enhancement of heat transfer was still significant. The self- sustaining flow was maintained at a long distance. The best performance was at the length of 36.85 times the diameter, increasing by 6.8% compared with a converging-diverging tube.

关 键 词： 强化传热 旋流片 缩放管 热阻

领　　域： [动力工程及工程热物理]