Journal of Power System Engineering (동력기계공학회지)

The Korean Society for Power System Engineering (한국동력기계공학회)
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Three-Dimensional Numerical Study on the Vortex Flow in a Horizontal Channels with High Viscous Fluid(2)

수평채널 내 고 점성유체의 볼텍스 유동에 관한 3차원 수치해석(2)

  • Received : 2015.04.27
  • Accepted : 2015.07.31
  • Published : 2015.08.31
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Abstract

TMixed convective flow in a bottom heated and top cooled rectangular channel can be significantly affected by the channel aspect ratio, Prandtl number, Reynolds number, Rayleigh number and angle of inclination. In such a mixed convection, the flow pattern plays an important role in various technological processes. In this study, a numerical investigation is carried out to explore mixed convection in a three-dimensional rectangular channel with bottom heated and top cooled uniformly. The three-dimensional governing equations are discretized using the finite volume method. In the range of low Reynolds number($0{\leq}Re{\leq}9.6{\times}10^{-2}$), the effects of the aspect ratio($2{\leq}AR{\leq}12$) and Gr/Re are presented and discussed. The longitudinal roll number in the channel is increased with increasing aspect ratio, and the roll number induced, regardless of the aspect ratio number, is even in the range of aspect ratios between 2 and 12, New vortex flow structure containing inclined longitudinal rolls is found, which is affected by aspect ratio and Reynolds number. The ratio Gr/Re is used to check the relative magnitudes of forced and natural convection in the mixed convective flow of high viscous fluid.

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References

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