Transactions of the Korean Society of Automotive Engineers (한국자동차공학회논문집)
- Volume 4 Issue 5
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- Pages.26-36
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- 1996
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- 1225-6382(pISSN)
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- 2234-0149(eISSN)
Turbulent Flow and Heat Transfer in an Annular Passage with Repeated-Ribbed Roughness on Both Walls
양측벽면에 반복돌출형 거칠기가 있는 이중관통로내의 난류운동과 열전달
Abstract
The fully developed turbulent momentum and heat transfer induced by the square-ribbed roughness elements on both the inner and outer wall surfaces in concentric annuli are studied analytically based on a modified turbulence model. The analytical results of the fuid flow are verified by experiment. The experiment is done with a pitot tube and a X-type hot wire anemometer to measure the time mean velocity profiles, zero shear stress positions, maximum velocity positions and friction factors, and etc. shown in Fig.1. The resulting momentum and heat transfer are discussed in terms of various parameters, such as the radius ratio, the relative roughness, the roughness density, Reynolds number, Nusselt bumber and Prand시 number. The study demonstrates that certain artificial roughness elements may be used to enhance heat transfer rates with advantage from the overall efficiency point of view by investigating turbulent flows and heat transfer in Fig.1.
Keywords
- Turbulent Flow;
- Heat Transfer;
- Square-Ribbed Surface Roughness;
- Concentric Annuli;
- Influence Coefficient
- 난류 유동;
- 열전달;
- 사각돌출형 표면조도;
- 이중동심관;
- 영향계수;