Korean Journal of Air-Conditioning and Refrigeration Engineering (설비공학논문집)
- Volume 10 Issue 2
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- Pages.193-201
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- 1998
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- 1229-6422(pISSN)
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- 2465-7611(eISSN)
Study on the flow characteristics and heat transfer enhancement on flat plate in potential core region of 2-dimensional air jet
포텐셜 코어내에 설치된 충돌평판상의 열전달증진 및 유동특성에 관한 연구
Abstract
A heat exchanging system employing the impinging air jet is still widely used In the various fields due to its inherent merits that include the easiness in engineering applications and the high heat and/or mass transfer characteristics. The purpose of this study is to investigate the enhancement of heat transfer and flow characteristics by placing a turbulence promoters in front of heat exchanging surface. In this study, a series of circular rods are placed at the upstream of a flat plate heat exchanger that is located at potential core region(H/W=2) of a two-dimensional impinging air jet. Heat transfer enhancement is achieved by inserting turbulence promoter that results in the flow acceleration and disturbance of boundary layer. The average Nusselt number of the flat plate with the turbulence promoters is found to be around 1.42 times higher than that of the flat plate without the turbulence promoters. Based on the results of flow visualization with a smoke wire, it is confirmed that the heat transfer enhancement is caused by the flow separation and disturbance of boundary layer by inserting the turbulence promoter.
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