대한기계학회논문집B (Transactions of the Korean Society of Mechanical Engineers B)

  • 제29권5호
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  • Pages.545-553
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  • 2005
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  • 1226-4881(pISSN)
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  • 2288-5324(eISSN)
대한기계학회 (The Korean Society of Mechanical Engineers)
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곡관덕트에 연결된 정사각단면 직관덕트에서 증류정상유동의 유동장내 유동특성

Flow Characteristics of Developing Laminar Steady Flows in a Straight Duct Connected to a Square Curved Duct

  • 손현철 (조선대학교 기계공학과)
  • 발행 : 2005.05.01
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초록

In the present study, The characteristics of developing steady laminar flows of a straight duct connected to a $180^{\circ}$ curved duct were examined In the entrance region through experimental measurement. Flow characteristics such as shear stress distributions, pressure distributions and friction coefficient experimentally in a square cross-sectional straight duct by using the PIV system. For the PIV measurement by particles produced from mosquito coils particles. The experimental data were obtained at 9 points dividing the test sections by 400mm. Experimental results can be summarized as follows. Critical Reynolds number, $Re_{cr}$ which indicates transition from laminar steady flow to transition steady flow was 2,150. Shear stress per unit length on the wall was stronger than that in the fully developed flow region. This was attributed to the fact that shear stress and pressure loss in the curvature of a duct were increased. Pressure distributions were gradually decreased irrespective of Reynolds number In the whole test section. This trends were in a good agreement with the reference results. Pipe friction coefficient in the steady state flow region was calculate from method of least squares. The co-relationship between fiction coefficient and Reynolds number was established as follow; ${\lambda}=56/Re$.

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참고문헌

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