• 한국산업융합학회 논문집
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• 제5권3호
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• pp.193-200
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• 2002

An experimental study was performed to study heat transfer characteristics for turbulent flow in an axisymmetric annuli. The air flow temperature and the local Nusselt number in turbulent flow were measured or calculated for Re=30,000, 40,000, 50,000, 60,000, 70,000 and 80,000. The local Nusselts number were compared to that obtained from Dittus-Boelter equation with turbulent flow. The results show that the flow enhances the heat transfer in the initial and exit portion of the test tube.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.408-413
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• 2003

Naphthalene sublimation technique is used to investigate the average and local heat transfer from the circular rod, and to determine the average and local heat transfer from the circular rod with and without square wing type mixing vane in axial flow. The experiments are performed for a circular rod and flat plate with and without mixing vane in wind tunnel. In comparison with flat plate and circular rod in axial flow, averaged Nusselts number is increased 2 times as the increase of Reynolds number with mixing vane. Longitudinal vortex induced by square wing type has the stronger vortex strength, so square wing type vortex generator shows an effect further in downstream.

• 대한기계학회논문집
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• 제16권1호
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• pp.112-121
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• 1992

본 연구에서는 상기 연구의 연장으로서 Prandtl수가 6.05인 내부발열유체가 경사진 정사각 난류자연대류유동, 온도분포 및 열전달량의 분포를 수치적인 방법으로 예측하였다. 벽면 깅이의 1/2를 특성길이로 하는 Rayleigh수의 범위는 1*$10^{6}$ ~1*$10^{9}$ 으로 선택하였으며 경사각도는 0˚, 15˚, 30˚및 45˚로 선택하였다.