Augmentation of Heat Transfer by two Dimensional Impinging Air Jet (Effect of Square Rib Width)

2차원(次元) 충돌분류(衝突噴流)의 열전달(熱傳達) 증진(增進)에 관(關)한 실험적(實驗的) 연구(硏究) (사각(四角) Rib폭(幅)의 효과(效果))

The impinging air jet system is still being used in the various fields with its inherent merits, that is, the easiness in engineering application and high heat transfer coefficients at stagnation point. The purpose of this study is augmentation of heat transfer without additional power in the rectangular air jet which impinges vertically to the heating surface. As a method of passive heat transfer augmentation in a two-Dimensional impinging jet, the transverse-repeated surface roughness of square cross-section is used. This paper deals with the experimental study on the characteristics of heat transfer at the x-direction in between nozzle exit and heating surface of flat plate, and that of ribbed plate. And this study also investigates the effect of square rib widths. The integral average heat transfer coefficient of ribbed plate is about 2.2 times larger than that of flat plate.