Korean Journal of Air-Conditioning and Refrigeration Engineering (설비공학논문집)

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Analysis of Convective Instability Induced by Buoyancy and Heat Transfer Characteristics for Natural Convetion in Nanofluids

나노유체의 부력에 의한 대류 불안정성 및 자연대류 열전달 특성 해석

  • 김제익 (서울대학교 응용화학부) ;
  • 강용태 (경희대학교 기계산업시스템공학) ;
  • 최창균 (서울대학교 응용화학부)
  • Published : 2004.08.01
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Abstract

The objective of the present study is to investigate the convective instability driven by buoyancy and the heat transfer characteristics of nanofluids. Using the property relations of nanofluid expressed as a function of the volume fraction of nanoparticles, the ratio of nanofluid Rayleigh number to basefluid one, f is newly defined. The results show that the density and the heat capacity of nanoparticles act as a destabilizing factor. With an increase of ${\gamma}$ which is the ratio of thermal conductivity of nanoparticles to that of basefluid, the thermal instability of nanofluid decreases but the heat transfer rate increases.

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References

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