Journal of the Society of Naval Architects of Korea (대한조선학회논문집)

The Society of Naval Architects of Korea (대한조선학회)
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Effects of Flow Acceleration on Drag Force and Wake Field of 2D Circular Cylinder

유입 유동의 가속도가 2D 원형실린더의 항력 및 후류에 미치는 영향

  • Son, Hyun A (Department of Structural Systems & CAE, Chungbuk National University) ;
  • Lee, Sungsu (School of Civil Engineering, Chungbuk National University) ;
  • Cho, Seong Rak (Korea Research Institute of Ships and Ocean Engineering)
  • 손현아 (충북대학교 토목시스템공학과) ;
  • 이승수 (충북대학교 토목공학부) ;
  • 조성락 (한국해양과학기술원 부설 선박해양플랜트연구소)
  • Received : 2019.07.17
  • Accepted : 2019.09.19
  • Published : 2019.12.20
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Abstract

Computational studies of accelerating flow around 2D Circular Cylinder was performed to investigate characteristics of wake field and drag forces. Previous studies had revealed that drag on the cylindrical body in accelerating flow is much greater than that in the flow with constant velocity; however, the underlying physics on the drag increase has not been clearly investigated. In order to investigate the drag increase and its relationship with wake development, this study employed a finite-volume based CFD code, Fluent 13.0 with k-ω SST model for turbulence effects. Inflows are modeled with varied accelerations from 0.4905 to 9.81m/s2. The drag computed in the present study is in good agreement with previous studies, and clearly shows the increase compared to the drag on the body in the flow with constant velocity. The results also show that drag crisis observed at high Reynolds number in the case of the flow with constant velocity is also found in the case of accelerating flow. The analysis for wake and recirculation length shows that conventional vortex shedding does not occur even at high Reynolds number and the drag increase is larger at higher acceleration.

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References

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