Korean Journal of Air-Conditioning and Refrigeration Engineering (설비공학논문집)

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Numerical Study on the Turbulent Flow in the 180^{\circ}$ Bends Decreasing Cross-sectional Aspect Ratio

단면의 폭이 감소하는 180^{\circ}$ 곡덕트 내 난류유동의 수치해석적 연구

  • 김원갑 (국민대학교 자동차공학전문대학원) ;
  • 최영돈 (고려대학교 기계공학과)
  • Published : 2002.12.01
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Abstract

This paper reports the characteristics of the three dimensional turbulent flow in the 180 degree bends with decreasing cross-sectional area by numerical method. Calculated pressure and velocity, Reynolds stress distributions are compared to the experimental data. Turbulence model employed are low Reynolds number k-epsilon model and algebraic stress model. The results show that the main vortex generated from the inlet part of the bend maintained to outlet of the bend because of the contraction of cross-sectional area. The rate of increase of turbulent kinetic energy through the bend are lower than that of mean flow. Secondary flow strength of the flow is lower about 60% than that of square duct flow.

Keywords

References

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