每扁管4个涡产生器式板芯传热与阻力研究

对扁管管片每单元４个涡产生器强化板芯进行了传热传质实验研究。实验结果表明当板间距一定，涡产生器高度一定时Ｎｕ数和ｆ数随涡产生器攻角的增大而增大。当板间距一定，涡产生器攻击角一定时Ｎｕ数和ｆ数随涡产生器高度的增大而增大，但当Ｈ／ｔｐ的比值小于一定值后，Ｎｕ数增加的不太显著。作了涡产生器式强化板芯与东风４Ｂ型机车中冷器板芯，在相同泵功率及相同温度条件下换热强度的比较，结果表明，换热增强２０％左右。

STUDY ON HEAT TRANSFER AND FRICTION CHARACTERISTICS OF SURFACE OF FLAT TUBE BANK FIN WITH FOUR DELT WINGLET VORTEX GENERATORS PER FLAT TUBE

An experimental study on heat transfer and friction characteristics of the surface of flat tube bank fin with four delt winglets per flat tube is made.The results show:when the plate space and the height of delt winglet vortex generator are given,Nusselt number and friction factor will rise with the increase of the attack angle of delt winglet vortex generator;when the plate space and the angle of attack of delt winglet vortexgenerator are given,Nusselt number and friction factor will rise with the increase of the height of delt winglet vortex generation.But when N/t p is smaller than a given value,the incrase of Nusselt number will be insignificant.The performance of the flat tube bank fin surface with punched delt winglets is compared with that of the intercooler used in Dongfen 4B locomative under the same temperafure and with the same pumping power.Results show that the heat transfer enhancement is about 20 percent.