Korean Journal of Air-Conditioning and Refrigeration Engineering (설비공학논문집)
- Volume 2 Issue 4
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- Pages.279-287
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- 1990
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- 1229-6422(pISSN)
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- 2465-7611(eISSN)
Augmentation of Heat Transfer for Circular Water Jet Impinging on a Cylindrical Inner Surface
충돌수분류(衝突水噴流)에 의한 원통내면(圓筒內面)에서의 열전달증진(熱傳達增進)에 관한 연구(硏究)
Abstract
An experimental study of the heat transfer characteristics between circular water jet and cylindrical inner surface is presented. The ratios of the semi-cylinder's inner diameter and the nozzle outlet diameter were varied parametrically, as were the Reynolds number and the supplementary water heights. The measurements showed that cirucmferential distribution of the heat transfer coefficient peaked at the stagnation point and, there occurred a kind of a secondary maximum of heat transfer that moved toward to stagnation point as the ratio d/D increased. The local heat transfer coefficient increases as the Reynolds number becomes larger, and the rate of increase is subjected to the influence of d/D & position of angle. Also, optimum heights of supplementary water which brings about the augmentation of heat transfer are S/D=1 for the stagnation point, the position of
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