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The Vertical Distribution of Longitudinal Velocity in Sharp Open Channel Bends

급변만곡부에서 종방향 유속의 연직분포

  • Lee, Kil-Seong (Shool of Civil, Urban & Geosystem Engineering, Seoul National University) ;
  • Kim, Tae-Won (Shool of Civil, Urban & Geosystem Engineering, Seoul National University) ;
  • Park, Jae-Hyeon (Department of Civil Engineering, Inje University)
  • 이길성 (서울대학교 지구환경시스템공학부) ;
  • 김태원 (서울대학교 지구환경시스템공학부) ;
  • 박재현 (인제대학교 토목공학과)
  • Published : 2006.12.31

Abstract

The characteristics of the longitudinal velocity in a $180^{\circ}$ constant-radius, recirculating laboratory channel were investigated. Three-dimensional velocity fields were measured using a side-looking ADV. The shortcomings of existing equations for longitudinal velocity are discussed. An eddy viscosity model is adopted in the downstream momentum equation. A mathematical equation was developed to describe the vertical distribution of longitudinal velocity. The comparisons of the longitudinal velocity show generally good agreement. It is found that the curvature change in the curved channel affects the vertical location of maximum velocity and the vertical profile of longitudinal velocity.

종방향 유속의 특성을 파악하기 위해서 중심각이 $180^{\circ}$인 순환수로에서 실험을 수행하였으며, 3차원 유속장 측정은 측방 음파 도플러 유속계를 이용하였다. 기존의 종방향 유속식들의 단점들을 검토하였다. 종방향 운동 방정식에 와점성 개념을 도입하여 새로운 종방향 유속의 연직분포 식을 개발하였다. 종방향 유속의 연직분포들을 비교한 결과 잘 일치함을 보여주고 있으며, 곡선수로에서 곡률의 변화는 종방향 유속의 연직분포 변화 및 최대 유속 발생 지점에 영향을 미치는 것을 발견하였다.

Keywords

References

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