Micro-Channel형 열교환기에 부착된 핀의 열접촉저항이 열전달 특성에 미치는 영향

Abstract

In this study, the effect of thermal contact resistance between pin-channel tubes on the heat transfercharacteristics was analytically examined around the channel tubes with the pins attached to two consecutivearranged channel pipes. The numerical results showed that the heat transfer coefficient decreased geometrically asthe thermal contact resistance increased, and the corresponding temperature change on the contact surfaceincreased as the thermal contact resistance increased. The thinner the pin, the more pronounced the geometricdrop in the heat transfer coefficient. It was confirmed that the higher the height of the pin, the higher was theheat transfer coefficient, however, the greater the size of the thermal contact resistance, the smaller was the heattransfer coefficient. It was found that the temperature change in the inner wall of the channel tube did notsignificantly affect the heat transfer characteristics owing to the thermal contact resistance. Furthermore, thevelocity of air at the entrance of the channel tube was proportional to the heat transfer coefficient due to adecrease in the convective heat resistance corresponding to an increase in the flow rate.