Journal of Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회논문집)

Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회)
권호 표지
DOI QR코드

DOI QR Code

A Study on Wave Responses of Vertical Tension-Leg Circular Floating Bodies

연직인장계류된 원형부유체의 파랑응답에 관한 연구

  • Lee, Kwang-Ho (Department of Civil Engineering, Nagoya University) ;
  • Kim, Chang-Hoon (Hyundai Engineering & Construction) ;
  • Kim, Do-Sam (Department of Civil Engineering, Korea Maritime University)
  • 이광호 (일본나고야대학 사회기반공학전공) ;
  • 김창훈 (현대건설 토목환경사업부 토목환경기술개발실) ;
  • 김도삼 (한국해양대학교 토목공학과)
  • Received : 2011.03.09
  • Accepted : 2011.06.08
  • Published : 2011.06.30
Download PDF
⟨ Previous Next ⟩

Abstract

In the present study, we proposed a new numerical wave tank model to analyze the vertical tension-leg circular floating bodies, using a 2-D Navier-Stokes solver. An IBM(Immersed Boundary Method) capable of handling interactions between waves and moving structures with complex geometry on a standard regular Cartesian grid system is coupled to the VOF(Volume of Fluid) method for tracking the free surface. Present numerical results for the motions of the floating body were compared with existing experimental data as well as numerical results based on FAVOR(Fractional Area Volume Obstacle Representation) algorithm. For detailed examinations of the present model, the additional hydraulic experiments for floating motions and free surface transformations were conducted. Further, the versatility of the proposed numerical model was verified via the numerical and physical experiments for the general rectangular floating bodies. Numerical results were compared with experiments and good agreement was archived.

본 연구에서는 규칙파동장에 있어서 인장계류된 원형부유체의 파랑응답해석에 2차원 Navier-Stokes solver에 기초한 새로운 수치파동수조모델을 제안하였다. 본 수치파동수조모델에서는 이동구조물과 유체와의 상호작용을 해석하기 위하여 직각좌표계에서 임의형상의 불투과경계를 갖는 구조물과 유체와의 연성해석이 가능한 IBM(Immersed Boundary Method)과 자유수면 추적을 위한 VOF(Volume of Fluid)법을 결합하였다. 부유체운동에 대한 수치결과를 기존의 FAVOR(Fractional Area Volume Obstacle Representation)법에 의한 계산결과 및 수리실험과 비교하였다. 게다가, 수치모델의 보다 자세한 검증을 위하여 원형부유체의 동요 및 자유수면변동에 관한 수리모형을 추가로 실시하였고, 제안된 수치모델의 범용성과 타당성을 검증하기 위하여 직사각형부유체에 대한 수치 및 수리실험도 병행하였다. 이로부터 추정된 수치계산결과는 실험결과를 잘 재현하고 있는 것으로 판단되었다.

Keywords

References

  1. 김도삼, 이광호, 최낙훈, 윤희면 (2004). 신형식 부방파제의 파랑제어에 관한 연구. 한국해안.해양공학회지, 16, 1-9.
  2. 이광호, 이상기, 신동훈, 김도삼 (2008). 복수 연직 주상구조물에 작용하는 비선형파력과 구조물에 의한 비선형파랑변형의 3차원 해석. 한국해안.해양공학회논문집, 20(1), 1-13.
  3. 이정열, 송무석 (2005). 부방파제를 이용한 원전항의 정온효과 수치해석. 한국해양환경공학회지, 8(1), 23-30.
  4. Ataur Rahman, M., Mizutani, N. and Kawasaki, K. (2006). Numerical modelling of dynamic responses and mooring forces of submerged floating breakwater. Coastal Engineering, 53, 799-815. https://doi.org/10.1016/j.coastaleng.2006.04.001
  5. Choi, J.L, Oberoi, R.C., Edward, J.R. and Rosati, J.A. (2007). An immersed boundary method for complex incompressible flows. Journal of Computational Physics, 224, 757-784. https://doi.org/10.1016/j.jcp.2006.10.032
  6. Gilmanov, A., Sotiropoulus, F. and Balaras, E. (2003). A general reconstruction algorithm for simulating flows with 3D, geometrically complex, moving bodies. Journal of Computational Physics, 191, 660-669. https://doi.org/10.1016/S0021-9991(03)00321-8
  7. Griffith, B.E. and Peskin, C.S. (2005). On the order of accuracy of the immersed boundary method: Higher order convergence rates for sufficiently smooth problems. Journal of Computational Physics, 208, 75-105. https://doi.org/10.1016/j.jcp.2005.02.011
  8. Hirt, C.W. and Nichols, B.D. (1981). Volume of Fluid(VOF) method for the dynamics of free boundaries. Journal of Computational Physics, 39, 201-225. https://doi.org/10.1016/0021-9991(81)90145-5
  9. Iwata, K., Kim, D.S., Asai, T. and Shimoda, N. (1990). Experimetnal study on wave breaking on a submerged floating body. Proceedings of Coastal Engineering, JSCE, 37, 604-608 (in Japanese). https://doi.org/10.2208/proce1989.37.604
  10. Kim, D.S. and Iwata, K. (1992). Dynamic behaviour of tautly moored semi-submerged structure with pressurized air-chamber and resulting wave transformation. Coastal Engineering in Japan, JSCE, 34(2), 223-242.
  11. Kojima, H., Yan, S., Irie, I. and Sekimoto, T. (1998). Hydraulic properties of a vertically-motioned hybrid wave absorbing structure. Proceedings of Coastal Engineering, JSCE, 45, 711-715 (in Japanese). https://doi.org/10.2208/proce1989.45.711
  12. Lee, K.H. and Mizutani, N. (2009). A numerical wave tank using directing-forcing immersed boundary method and its application to wave force on a horizontal cylinder. Coastal Engineering Journal, 15(1), 27-48.
  13. Lima e Silva, A.L.F., Silveria-Neto, A. and Damasceno, J.J.R. (2003). Numerical simulation of two dimensional flows over a circular cylinder using the immersed boundary method. Journal of Computational Physics, 351, 351-370.
  14. Mohd-Yusof, J. (1997). Combined immersed boundaries/B-splines methods for simulations in complex geometries. CTR Annual Research Briefs, NASA Ames / Stanford University.
  15. Nakamura, T., Kamikawa, H., Kohno, T. and Makimoto, K. (2000). Performance and wave force characteristics of a double curtainwalled breakwater with different drafts. Proceedings of Coastal Engineering, JSCE, 47, 951-955 (in Japanese). https://doi.org/10.2208/proce1989.47.951
  16. Peskin, C.S. (1977). Numerical analysis of blood flow in the heart. Journal of Computational Physics, 25, 220-252. https://doi.org/10.1016/0021-9991(77)90100-0