Journal of Ocean Engineering and Technology (한국해양공학회지)

Korean Society of Ocean Engineers (한국해양공학회)
권호 표지
DOI QR코드

DOI QR Code

Dynamic Behavior Assessment of OC4 Semi-submersible FOWT Platform Through Morison Equation

  • Chungkuk Jin (Department of Ocean Engineering and Marine Sciences, Florida Institute of Technology) ;
  • Ikjae Lee (Department of Ocean Engineering, Texas A&M University) ;
  • JeongYong Park (Department of Ocean Engineering, Texas A&M University) ;
  • MooHyun Kim (Department of Ocean Engineering, Texas A&M University)
  • Received : 2023.09.20
  • Accepted : 2023.11.21
  • Published : 2023.12.31
Download PDF
⟨ Previous Next ⟩

Abstract

This paper proposes an effective inertia coefficient (EIC) in the Morison equation for better wave-force calculations. The OC4 semi-submersible floating offshore wind turbine (FOWT) platform was considered to test the feasibility. Large diffraction at large Keulegan-Carpenter (KC) numbers and the interaction between columns can result in errors in estimating the wave force using the Morison equation with a theoretical inertia coefficient, which can be corrected by the EIC as a function of the wave period and direction. The horizontal and vertical wave forces were calculated using the Morison equation and potential theory at each column, wave period, and wave direction. The EICs of each column were then obtained, resulting in a minimal difference between the Morison inertia force and the wave excitation force by the potential theory. The EICs, wave forces, phase angles, and dynamic motions were compared to confirm the feasibility of an EIC concept under regular and random waves.

Keywords

References

  1. Abbasnia, A., & Soares, C. G. (2018). Fully nonlinear simulation of wave interaction with a cylindrical wave energy converter in a numerical wave tank. Ocean engineering, 152, 210-222. https://doi.org/10.1016/j.oceaneng.2018.01.009
  2. Boccotti, P., Arena, F., Fiamma, V., & Romolo, A. (2013). Two small-scale field experiments on the effectiveness of Morison's equation. Ocean engineering, 57, 141-149. https://doi.org/10.1016/j.oceaneng.2012.08.011
  3. Chakrabarti, S. K., & Tam, W. A. (1975). Interaction of waves with large vertical cylinder. Journal of Ship Research, 19(01), 23-33. https://doi.org/10.5957/jsr.1975.19.1.23
  4. Chang, S., Huang, W., Sun, H., & Li, L. (2019). Numerical investigation of secondary load cycle and ringing response of a vertical cylinder. Applied Ocean Research, 91, 101872. https://doi.org/10.1016/j.apor.2019.101872
  5. Chen, B., Lu, L., Greated, C. A., & Kang, H. (2015). Investigation of wave forces on partially submerged horizontal cylinders by numerical simulation. Ocean engineering, 107, 23-31. https://doi.org/10.1016/j.oceaneng.2015.07.026
  6. Chung, J. S. (2018). Morison equation in practice and hydrodynamic validity. International Journal of Offshore and Polar Engineering, 28(01), 11-18. https://doi.org/10.17736/ijope.2018.jc740
  7. Dafnakis, P., Bhalla, A. P. S., Sirigu, S. A., Bonfanti, M., Bracco, G., & Mattiazzo, G. (2020). Comparison of wave-structure interaction dynamics of a submerged cylindrical point absorber with three degrees of freedom using potential flow and computational fluid dynamics models. Physics of Fluids, 32(9). https://doi.org/10.1063/5.0022401
  8. Faltinsen, O. (1993). Sea loads on ships and offshore structures (Vol. 1). Cambridge university press.
  9. Gonzalez, G. G., Urban, A. M., Horcas, S. G., Roqueta, L. V. I., & Blanco, S. H. (2021). Evaluation of a lowfidelity hydrodynamic modelling approach for a floating wind turbine mounted on an enhanced spar. Journal of Physics: Conference Series, 2018(1), [012019]. https://doi.org/10.1088/1742-6596/2018/1/012019
  10. Jin, C. (2022). Comparison of Potential Theory and Morison Equation for Deformable Horizontal Cylinders. Sustainable Marine Structures, 4(2), 1-10. https://doi.org/10.36956/sms.v4i2.492
  11. Jin, C., Bakti, F. P., & Kim, M. (2021). Time-domain coupled dynamic simulation for SFT-mooring-train interaction in waves and earthquakes. Marine Structures, 75, 102883. https://doi.org/10.1016/j.marstruc.2020.102883
  12. Jin, C., Kim, G.-J., Kim, S.-J., Kim, M., & Kwak, H.-G. (2023). Discrete-module-beam-based hydro-elasticity simulations for moored submerged floating tunnel under regular and random wave excitations. Engineering Structures, 275, 115198. https://doi.org/10.1016/j.engstruct.2022.115198
  13. Kim, M., & Chen, W. (1994). Slender-body approximation for slowly-varying wave loads in multi-directional waves. Applied Ocean Research, 16(3), 141-163. https://doi.org/10.1016/0141-1187(94)90025-6
  14. Kvittem, M. I., Bachynski, E. E., & Moan, T. (2012). Effects of hydrodynamic modelling in fully coupled simulations of a semi-submersible wind turbine. Energy Procedia, 24, 351-362. https://doi.org/10.1016/j.egypro.2012.06.118
  15. Lee, C.-H. (1995). WAMIT theory manual (Report No. 95-2). Massachusetts Institute of Technology, Department of Ocean Engineering.
  16. Li, Y. S., Zhan, S., & Lau, S. (1997). In-line response of a horizontal cylinder in regular and random waves. Journal of Fluids and Structures, 11(1), 73-87. https://doi.org/10.1006/jfls.1996.0067
  17. Lin, H., Xiang, Y., Yang, Y., & Chen, Z. (2018). Dynamic response analysis for submerged floating tunnel due to fluid-vehicle-tunnel interaction. Ocean Engineering, 166, 290-301. https://doi.org/10.1016/j.oceaneng.2018.08.023
  18. Morison, J., Johnson, J. W., & Schaaf, S. A. (1950). The force exerted by surface waves on piles. Journal of Petroleum Technology, 2(05), 149-154. https://doi.org/10.2118/950149-G
  19. Paulsen, B. T., Bredmose, H., Bingham, H. B., & Jacobsen, N. G. (2014). Forcing of a bottom-mounted circular cylinder by steep regular water waves at finite depth. Journal of Fluid Mechanics, 755, 1-34. https://doi.org/10.1017/jfm.2014.386
  20. Robertson, A., Jonkman, J., Masciola, M., Song, H., Goupee, A., Coulling, A., & Luan, C. (2014). Definition of the semi-submersible floating system for phase II of OC4. United States. https://doi.org/10.2172/1155123
  21. Takata, T., Takaoka, M., Goncalves, R. T., Houtani, H., Yoshimura, Y., Hara, K., Oh, S., Dotta, R., Malta, E. B., Iijima, K., & H. Suzuki (2021). Dynamic Behavior of a Flexible Multi-Column FOWT in Regular Waves. Journal of Marine Science and Engineering, 9(2), 124. https://doi.org/10.3390/jmse9020124