• Title/Summary/Keyword: 비등방 부력

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A Hybrid Turbulence Model for Prediction of Buoyancy-Driven Turbulent Thermal Convection Flow (부력에 의한 난류 열대류의 혼성 난류모델)

  • 김태규;성형진
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.17 no.8
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    • pp.2069-2078
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    • 1993
  • The buoyancy-driven turbulent thermal convection is predicted using an anisotropic hybrid turbulence model, which is incorporated with a low Reynolds k-.epsilon. turbulence model and an anisotropic buoyant part of algebraic stress model(ASM). The numerical predictions are compared with the Davidson's model,(1) the full ASM and the experimental results of Cheesewright et al.(2) All the models are shown to predict good agreements with the experiments for the averaged turbulence quantities. It is found that the effect of an anisotropic part on the Reynolds stress and the turbulent heat fluxes is substantial. In this study, the present hybrid model gives a fairly reasonable prediction in terms of the computational accuracy, convergence and stability. The contribution of an anisotropic buoyant part to turbulent heat fluxes are also scrutinized over the range of Rayleigh numbers $(4.79{\times}10^{10}{\le}Ra{\le}7.46{\times}10^{10}).$