나노유체의 부력에 의한 대류 불안정성 및 자연대류 열전달 특성 해석

Analysis of Convective Instability Induced by Buoyancy and Heat Transfer Characteristics for Natural Convetion in Nanofluids

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

초록

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.

키워드

참고문헌

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