Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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Characteristics of Near Wake Behind a Circular Cylinder with Serrated Fins (I) - Mechanism of Vortex Shedding -

톱니형 휜이 부착된 원주의 근접후류특성 연구 (I) - 와유출 메카니즘의 특성변화 규명 -

  • Ryu, Byeong-Nam (Dept.of Mechanical Engineering, Graduate School of Busan National University) ;
  • Kim, Gyeong-Cheon (Mechanical Technology Research Center, Dept.of Mechanical Engineering, Busan National University) ;
  • Bu, Jeong-Suk
  • Published : 2002.08.01
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Abstract

An experimental study is performed to investigate the characteristics of near wake behind a circular cylinder with serrated fins using the constant temperature anemometer and through flow visualization. Previous report(Boo et al., 2001) shows that there are three different modes in vortex shedding behavior. This paper is focused on the identification of the physical reasons why the difference iss occured in vortex shedding. The through flow velocity crossing fins decreases as increasing fin height and decreasing fin pitch mainly due to the flow resistence. Vortex shedding is affected strongly by velocity distribution around fin tube, especially by the velocity gradient. The velocity distribution at X/d=0.0 has lower gradient with increasing freestream velocity and fin height and decreasing fin pitch. Those differences in velocity gradients generate different vortex shedding mechanism.

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References

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