# 레이놀즈 수가 낮은 영역에서 와류발생기를 적용한 핀-관 열교환기 성능평가

• Kwak Kyung-Min (School of Mechanical and Automotive engineering, Kyungil University) ;
• Song Gil-Dal (Department of Mechanical Engineering, Yokohama National University)
• 곽경민 (경일대학교 기계자동차학부) ;
• 송길달 (일본 요코하마 국립대학교 기계공학과)
• Published : 2006.02.01

#### Abstract

The present paper reports the method for evaluation of heat-transfer performance of finned tube heat exchangers in a low Reynolds number regime (Re = $160\~800$) and also reports the data of heat transfer and pressure loss taken from a finned tube heat exchanger with/without vortex generators (VGs) installed as a heat-transfer enhancement device. The evaluation is based on the modified single blow method conducted in a specially designed low Reynolds number duct. Three different test core geometries, i.e., fin only, fin-tube without VGs and that with VGs, are studied here. The data of heat transfer and pressure loss taken from the fin only geometry agree well with the empirical correlations, thus validating the present method as used for low Reynolds number regime. The data taken from the finned tube geometries with and without VGs are presented and compared to examine the effect of VGs in the low Reynolds number regime.

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