딤플과 돌출이 설치된 수평채널의 열전달 및 압력강하 특성에 관한 수치해석적 연구

Abstract

Abstract: In this study, numerical analyses were performed on pressure drop and heat transfer characteristics in a rectangular horizontal channel with dimple and protrusion arrays of different height. Thedimples/protrusions were installed at both top and bottom walls of the rectangular channel. The dimple andprotrusion depths are 0.125, 0.2, 0.25, 0.3, and 0.375 times diameter. In case of the dimple, the highest Nusselt number occurred at the rear side of the dimple, and the average Nusselt number tended to decreaseslightly with increase of depth. In case of protrusion, on the other hand, the highest Nusselt number occurred at the front side of the protrusion, and the average Nusselt number was increased with the increase of height. In both dimple and protrusion, the average Nusselt number and pressure drop were increased with the increase of velocity. Performance factor was decreased with the increase of velocity, andit was found that the best performance factor was obtained in the low velocity region.