Abstract
Among tubular heat exchangers, fin-tube types are the most widely used in refrigeration and air-conditioning equipment. Efforts to enhance the performance of these heat exchangers included variations in the fin shape from a plain fin to a slit and louver type. In the context of heat transfer augmentation, the performance of vortex generators has also been investigated. Delta winglet vortex generators have recently attracted research interest, partly due to experimental data showing that their addition to fin-tube heat exchangers considerably reduces pressure loss at heat transfer capacity of nearly the same level. The efficiency of the delta winglet vortex generators widely varies depending on their size and shape, as well as the locations where they are implemented. In this paper, the flow field around delta winglet vortex generators in a common flow up arrangement was analyzed in terms of flow characteristics and heat transfer using computational fluid dynamics methods. Flow mixing due to vortices and delayed separation due to acceleration influence the overall fin performance. The fin with delta winglet vortex generators exhibited a pressure loss lower than that of a plain fin, and the heat transfer performance was enhanced at high air velocity or Reynolds number.
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Recommended by Associate Editor Man-Yeong Ha
Seong Won Hwang received his Master’s degree for Mechanical Engineering at the Pusan National University in 2010. He is currently a Ph.D. candidate. His research interests include heat exchanger performance tests and CFD analyses. He is currently working on heat exchangers with offset strip fins and vortex generators.
Dong Hwan Kim received his Master’s degree for Mechanical Engineering at the Pusan National University in 2011. He works on heat transfer enhancement and its application to energy systems.
June Kee Min studied in KAIST and received his Ph.D. in 1999. He worked for LG Electronics and Samsung Electronics as a thermo-fluid engineer for over 10 years. He joined the Rolls-Royce Pusan National University Technology Center in 2008. His research interests mainly include CFD-based fluid flow and heat transfer problems, such as heat exchangers, HVAC&R, and the thermal management of power storage systems.
Ji Hwan Jeong received his Ph.D. from the KAIST in 1995. His post-doctoral research was conducted at the Technology Centre in Aerodynamics and Heat Transfer at Oxford University. After three years of research at the Korea Atomic Energy Research Institute, he joined the faculty of the School of Mechanical Engineering at Pusan National University. His research interests include multi-phase flow, nuclear safety, heat exchangers, heat pump, and computational fluid dynamics. He has also consulted for the nuclear and air conditioner industries.
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Hwang, S.W., Kim, D.H., Min, J.K. et al. CFD analysis of fin tube heat exchanger with a pair of delta winglet vortex generators. J Mech Sci Technol 26, 2949–2958 (2012). https://doi.org/10.1007/s12206-012-0702-2
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DOI: https://doi.org/10.1007/s12206-012-0702-2