대한기계학회논문집 (Transactions of the Korean Society of Mechanical Engineers)
- 제9권6호
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- Pages.767-776
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- 1985
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- 1225-5963(pISSN)
DOI QR Code
비정상 열확산 현상 의 실험적 연구
Experimental study of unsteady thermally stratified flow
- 발행 : 1985.11.01
초록
본 연구에서는 초기 조건(입구 R
Unsteady thermally stratified flow caused by two-dimensional surface discharge of warm water into a oblong channel was investigated. Experimental study was focused on the rapidly developing thermal diffusion at small Richardson number. The basic objective were to study the interfacial mixing between a flowing layer of warm water and an underlying body of cold water and to accumulate experimental data to test computational turbulence models. Mean velocity field measurements were carried out by using NMR-CT (Nuclear Magnetic Resonance-Computerized Tomography). It detects quantitative flow image of any desired section in any direction of flow in short time. Results show that at small Richardson number warm layer rapidly penetrates into the cold layer because of strong turbulent mixing and instability between the two layers. It is found that the transfer ofheat across the interface is more vigorous than that of momentum. It is also proved that the NMR-CT technique is a very valuable tool to measure unsteady three dimensional flow field.
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