• 제목/요약/키워드: 열역학적 국소평형

검색결과 1건 처리시간 0.018초

다공성 물질 안에서의 자연대류 현상에 대한 열역학적 국소평형상태 가정의 고찰 (An Investigation on Local Thermodynamic Equilibrium Assumption of Natural Convection in a Porous Medium)

  • 김인선;남진현;김찬중
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 추계학술대회논문집B
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    • pp.112-117
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    • 2000
  • A numerical study on natural convection in a vertical square cavity filled with a porous medium is carried out with Brinkman-Forchheimer-extended Darcy flow model, and the validity of local thermodynamic equilibrium assumption is studied. The local thermodynamic equilibrium refers to the state in which a single temperature can be used to describe a heat transfer process in a multiphase system. With this assumption, the analysis is greatly simplified because only one equation is needed to describe the heat transfer process. But prior to using this assumption, it is necessary to know in what conditions the assumption can be used. The numerical results of this study reveal that large temperature difference between fluid phase and solid phase exists near wall region, paticularily when the convection becomes dominant over conduction. And the influence of flow parameters such as fluid Rayleigh number, fluid Prandtl number, dimensionless particle diameter and conductivity ratio are investigated.

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