자유표면 밑을 전진하는 원주 주위의 유동에 관한 연구

다국어 초록 (Multilingual Abstract)

The flow around a circular cylinder advancing beneath the free is numerically investigated using a VOF method. The simulations cover Froude numbers in the range of 0.2~0.6 and gap ratios (h/d) in the range of 0.1~2.0, where h is the distance from the free surface to a cylinder, and d is the diameter of a cylinder at Reynolds number 180. It is observed that the vortex suppression effect surface deformation increase as the gap ratio decreases or the Froude number increase. The most important results of the present study are as follows. The proximity of the free surface causes an initial increase in the Strouhal number and drag coefficient, and the maximum Strouhal number and drag coefficient occur in the range of 0.5~0.7. However, this trend reverses as the gap ratio becomes small, and the life coefficient increases downward as the gap ratio decreases.

참고문헌 (Reference)

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