Journal of computational fluids engineering (한국전산유체공학회지)

Korean Society of Computational Fluids Engineering (한국전산유체공학회)
권호 표지

NUMERICAL SIMULATION OF THE FLOW CHARACTERISTICS INSIDE A U-TYPE TUBE

U-자형 곡관내의 유동특성에 대한 수치해석적 연구

  • 고동훈 (영남대학교 대학원 기계공학과) ;
  • 강동진 (영남대학교 기계공학부) ;
  • 송동주 (영남대학교 기계공학부)
  • Published : 2009.09.30
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Abstract

A numerical study of the flow characteristics inside a U-type circular tube is carried out in this paper. The numerical simulations carried out by using a Navier-Stokes code which is commercially available. Before detailed numerical simulations, validation of present numerical approach is made by comparing numerical solutions with experimental data. Numerical simulations are performed to study the effect of curvature on the flow characteristics inside a U-type tube. Numerical solutions show that a significant effect on the secondary flow structure in the cross section of the tube, especially in the curved section is shown when the curvature ratio, ratio of curvature to tube diameter, is smaller than about 3.5. As the curvature ratio decreases below 3.5, a counter rotating vortex is found below the primary vortex in the cross section of the tube. Another dramatic change of the flow structure is the formation of streamwise separation zone when the curvature ratio is decreased below 1.25.

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References

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