Flow Structures Around a Freely-falling, Rectangular Cylinder

자유 낙하하는 사각 실린더 주위의 유동 구조

  • Jeon, Chung-Ho (Dept. of Naval Architect and Ocean Engineering, Pusan National University) ;
  • Lee, Chang-Yeol (Dept. of Naval Architect and Ocean Engineering, Pusan National University) ;
  • Yoon, Hyun-Sik (Advanced Ship Engineering Research Center, Pusan National University)
  • 전충호 (부산대학교 조선해양공학과) ;
  • 이창열 (부산대학교 조선해양공학과) ;
  • 윤현식 (부산대학교 첨단조선공학연구센터)
  • Received : 2010.06.14
  • Accepted : 2010.09.28
  • Published : 2010.10.31

Abstract

The flow around a two-dimensional, rectangular cylinder that is freely falling in a channel was simulated using the immersed boundary method with direct forcing to determine the interactions between the fluid and the structure. The results of the present study were in good agreement with previous experimental results. Regardless of the H/L ratio (where H and L are the height and width of the rectangular cylinder, respectively), the flow structures had essentially the same pattern as the two symmetrical circulations that form about the horizontal center of the cylinder, with those centers located at each lateral position near the wake. When the cylinder approaches very close to the bottom, a jet-like flow appeared between the bottom of the rectangular cylinder and the channel. When the jet-like flow goes through the channel, surrounding fluids are sucked into this jet, forming the secondary vortices.

Keywords

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