Abstract
The multi-body system has been a popular form for offshore operations in terms of high efficiency. The wind effects are crucial which directly affect the relative positions of floating bodies and operating security. In this study, the aerodynamic characteristics for two coupled semi-submersibles were analyzed in a wind tunnel to fill the gaps in literature related to the wind sheltering on offshore platforms. The influences of separation distance were also investigated. According to the results, substantial shielding effects were observed and wind forces on the shielded vessel decreased dramatically: a reduction in the transverse force could be up to 74%. Moreover, the longitudinal wind load was amplified by the platform abreast in a side-by-side configuration. As expected, the interference level became more pronounced with a decreasing separation distance. For cases in which wind interaction decayed rapidly with distance, logarithmic functions were preferable for describing the relationship between them. Whereas linear fitting was reasonable for the transverse wind force when there was still evident sheltering at a quite large distance. The length of shielding area was another important factor that there was approximately a linear relationship between it and the shielding level for two platforms in close proximity at various wind attack angles. Based on the two parameters, a preliminary wind loads estimation method considering shielding effects was proposed. This approach can aid the industry to have a qualitative assessment of wind sheltering especially at early stages.
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Cho, S., Hwang, S., Jung, J., Sung, H., Park, B. and Vazquez-Hernandez, A., 2018. Estimation of wind and current load on offshore structures using wind tunnels and CFD, Proceedings of the Offshore Technology Conference, Houston, Texas, USA, pp. 15.
Choi, Y.M., Nam, B.W., Hong, S.Y., Jung, D.W. and Kim, H.J., 2018. Coupled motion analysis of a tension leg platform with a tender semi-submersible system, Ocean Engineering, 156, 224–239.
Croonenborghs, E., Sauder, T., Fouques, S. and Reinholdtsen, S.A., 2013a. CFD prediction of wind and current loads on a complex semi-submersible geometry, Ship Technology Research, 60(3), 118–127.
Croonenborghs, E., Sauder, T., Fouques, S. and Reinholdtsen, S.A., 2013b. Comparison of various methods for the assessment of wind and current loads on a semi-submersible platform, Proceedings of 2013 OTC Brasil, Rio de Janeiro, Brazil.
Deck, S., Gand, F., Brunet, V. and Khelil, S.B., 2014. High-fidelity simulations of unsteady civil aircraft aerodynamics: Stakes and perspectives, Application of zonal detached eddy simulation, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 372(2022), 20130325.
DNV, 2007. Environmental Conditions and Environmental Loads, Recommended Practice, Norway.
Dong, Q., Lu, H.N., Yang, J.M. and Guo, X.X., 2019. Dynamic gangway responses between TLP and semi-submersible platform during tender-assisted drilling, Marine Structures, 67, 102645.
Dong, Q., Yang, J.M. and Guo, X.X., 2020. Measurements of current loads on side-by-side semi-submersibles in a wind tunnel, Ocean Engineering, 201, 107126.
Freathy, P.E. and Vickery, B.J., 1986. Wind loads on semisubmersible offshore platforms, Proceedings of 1986 Offshore Technology Conference, Houston, Texas.
Fujiwara, T., Ueno, M. and Ikeda, Y., 2005. A new estimation method of wind forces and moments acting on ships on the basis of physical component models, Journal of the Japan Society of Naval Architects and Ocean Engineers, 2, 243–255.
Fujiwara, T., Yukawa, K., Sato, H., Otsubo, K. and Taniguchi, T., 2012. Wind effect estimation in side by side offloading operation for FLNG and LNG carrier ships, Proceedings of the ASME 2012 31st International Conference on Ocean, Offshore and Arctic Engineering, ASME, Rio de Janeiro, Brazil, pp. 71–78.
Furnes, G.K., 1998. Numerical simulations of wind forces on Troll B, Marine Structures, 11(7–8), 273–289.
Ganesan, T.S. and Sen, D., 2016. Time domain simulation of side-by-side floating bodies using a 3D numerical wave tank approach, Applied Ocean Research, 58, 189–217.
Goedegebuure, B. and Willemsen, E., 2003. Wind Tunnel Investigation on Shielding During Tandem Offloading, LST-2003-05, DNW, Markenesse.
Hansen, K.S., Barthelmie, R.J., Jensen, L.E. and Sommer, A., 2012. The impact of turbulence intensity and atmospheric stability on power deficits due to wind turbine wakes at Horns Rev wind farm, Wind Energy, 15(1), 183–196.
Kim, J.W., Jang, H., Xu, W., Shen, Z.R., Kara, M., Yeon, S. and Yan, H.M., 2018. Numerical modeling of neutrally-stable and sustainable atmospheric boundary layer for the wind load estimation on an offshore platform, Proceedings of the ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering, ASME, Madrid, Spain.
König, M., González, D.F., Abdel-Maksoud, M. and Düster, A., 2017. Numerical investigation of the landing manoeuvre of a crew transfer vessel to an offshore wind turbine, Ships and Offshore Structures, 12(S1), S115–S133.
Koop, A., Klaij, C. and Vaz, G., 2010. Predicting wind loads for FPSO tandem offloading using CFD, Proceedings of ASME 2010 29th International Conference on Ocean, Offshore and Arctic Engineering, ASME, Shanghai, China, pp. 533–546.
Kunkyebe, S. and Georgiev, Y., 2015. Optimal Working Conditions of A Floatel Along An FPSO, MSc. Thesis, Chalmers University of Technology, Göteborg, Sweden.
OCIMF, 1994. Predictions of Wind and Current Loads on VLCCs, Oil Companies International Marine Forum.
Ren, N.X., Li, Y.G. and Ou, J.P., 2012. The wind-wave tunnel test of a tension-leg platform type floating offshore wind turbine, Journal of Renewable and Sustainable Energy, 4(6), 063117.
Schewe, G., 1983. On the force fluctuations acting on a circular cylinder in crossflow from subcritical up to transcritical Reynolds numbers, Journal of Fluid Mechanics, 133, 265–285.
Schrijvers, P., Xu, W., Koop, A. and Yoo, D., 2018. Current status of wind load calculations with CFD, Proceedings of the 28th International Ocean and Polar Engineering Conference, ISOPE, Sapporo, Japan.
SIGTTO, 2007. Prediction of Wind Loads on Large Liquefied Gas Carriers, Society of International Gas Tanker and Terminal Operators, London.
Tannuri, E.A., Fucatu, C.H., Rossin, B.D., Montagnini, R.C.B. and Ferreira, M.D., 2010. Wind shielding effects on DP system of a shuttle tanker, Proceedings of the ASME 2010 29th International Conference on Ocean, Offshore and Arctic Engineering, ASME, Shanghai, China, pp. 143–149.
Tian, W., Ozbay, A. and Hu, H., 2019. A wind tunnel study of wind loads on a model wind turbine in atmospheric boundary layer winds, Journal of Fluids and Structures, 85, 17–26.
Türk, M. and Emeis, S., 2010. The dependence of offshore turbulence intensity on wind speed, Journal of Wind Engineering and Industrial Aerodynamics, 98(8–9), 466–471.
Willemsen, E., Augenstein, A. and Takens, J., 2008. Wind Tunnel Investigation on the Wind and Current Load Interference Effects for the OO2 JIP, LST-2008-28, DNW.
Wnęk, A.D., Paço, A., Zhou, X.Q., Sutulo, S. and Soares, C.G., 2015. Experimental study of aerodynamic loads on an LNG carrier and floating platform, Applied Ocean Research, 51, 309–319.
Xu, W., Schrijvers, P., Koop, A. and Ryu, D., 2018. Wind shielding estimation of a vessel in side by side configuration using disturbed velocity field from CFD, Proceedings of the 23rd Offshore Symposium, SNAME, Houston, Texas.
Yeon, S., Jang, H., Kim, J.W., Kim, J., Nam, B.W., Huang, Z.J., O’ Sullivan, J., Kim, H.J. and Hong, S. Y., 2019. Numerical modeling practice and verification of the wind load estimation for FPSO and semi-submersible, Proceedings of the 38th International Conference on Ocean, Offshore and Arctic Engineering, ASME, Glasgow, Scotland, UK.
Yi, C., Li, D., Bai, X.P., Zhang, C. and Zheng, W.T., 2015. Experimental research of wind loads on a FPSO, Proceedings of the 25th International Ocean and Polar Engineering Conference, ISOPE, Kona, Hawaii, USA.
Yoo, D., Park, J.C., Schrijvers, P. and Koop, A., 2018. Predicting wind loads on single vessels and in side by side offloading configuration for FPSO and shuttle tanker using CFD, Proceedings of the 28th International Ocean and Polar Engineering Conference, ISOPE, Sapporo, Japan.
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This study was supported by the Ministry of Industry and Information Technology of China (Grant No. [2016] 546) and Shanghai Innovation Action Plan of Science and Technology (Grant No. 19DZ1207300).
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Dong, Q., Guo, Xx., Yang, Jm. et al. Measurements of Wind Loads on Side-by-Side Semi-Submersibles in A Wind Tunnel. China Ocean Eng 35, 531–543 (2021). https://doi.org/10.1007/s13344-021-0048-6
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DOI: https://doi.org/10.1007/s13344-021-0048-6