Wind and Structures

  • 제6권5호
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  • Pages.347-356
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  • 2003
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  • 1226-6116(pISSN)
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  • 1598-6225(eISSN)
테크노프레스 (Techno-Press)
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Drag reduction of a circular cylinder at subcritical flow regime using base shield plates

  • El-Khairy, Nabil A.H. (Department of Civil Engineering, University of Jordan)
  • 투고 : 2003.06.02
  • 심사 : 2003.10.15
  • 발행 : 2003.10.25
⟨ 이전 논문 다음 논문 ⟩

초록

Experimental studies on drag reduction of a circular cylinder of diameter D were conducted in the subcritical flow regime at Reynolds numbers in the range $4{\times}10^4{\leq}Re{\leq}10^5$. To shield the cylinder rear surface from the pressure deficit of the unsteady vortex generation in the near wake, two shield plates were attached downstream of the separation points to form a cavity at the base region. The chord of the shield plates, L, ranged from 0.22 to 1.52 D and the cavity width, G, was in the range from 0 to 0.96 D. It is concluded that significant drag reductions from that of a plain cylinder may be achieved by proper sizing of the shield plates and the base cavity. The study shows that using a pair of shield plates at G/D of 0.86 and angular position ${\theta}$ of ${\pm}121^{\circ}$ results in a configuration with percentage drag reduction of 40% for L/D of 0.5, and 55% for L/D of 1.0.

키워드

참고문헌

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