Ocean Systems Engineering

  • 제11권1호
  • /
  • Pages.17-42
  • /
  • 2021
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  • 2093-6702(pISSN)
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  • 2093-677X(eISSN)
테크노프레스 (Techno-Press)
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Aerodynamic behaviour of double hinged articulated loading platforms

  • Zaheer, Mohd Moonis (Department of Civil Engineering, Z.H. College of Engg. & Tech., AMU) ;
  • Hasan, Syed Danish (Department of Civil Engineering, Z.H. College of Engg. & Tech., AMU) ;
  • Islam, Nazrul (Department of Civil Engineering, Jamia Millia Islamia) ;
  • Aslam, Moazzam (Civil Engineering Section, University Polytechnic, AMU)
  • 투고 : 2020.11.17
  • 심사 : 2021.02.27
  • 발행 : 2021.03.25
⟨ 이전 논문 다음 논문 ⟩

초록

Articulated loading platforms (ALPs) belongs to a class of offshore structures known as compliant. ALP motions have time periods falling in the wind excitation frequency range due to their compliant behaviour. This paper deals with the dynamic behavior of a double hinged ALP subjected to low-frequency wind forces with random waves. Nonlinear effects due to variable submergence, fluctuating buoyancy, variable added mass, and hydrodynamic forces are considered in the analysis. The random sea state is characterized by the Pierson-Moskowitz (P-M) spectrum. The wave forces on the submerged elements of the platform's shaft are calculated using Morison's Equation with Airy's linear wave theory ignoring diffraction effects. The fluctuating wind load has been estimated using Ochi and Shin wind velocity spectrum for offshore structures. The nonlinear dynamic equation of motion is solved in the time domain by the Wilson-θ method. The wind-structure interactions, along with the effect of various other parameters on the platform response, are investigated. The effect of offset of aerodynamic center (A.C.) with the center of gravity (C.G.) of platform superstructure has also been investigated. The outcome of the analyses indicates that low-frequency wind forces affect the response of ALP to a large extent, which otherwise is not enhanced in the presence of only waves. The mean wind modifies the mean position of the platform surge response to the positive side, causing an offset. Various power spectral densities (PSDs) under high and moderate sea states show that apart from the significant peak occurring at the two natural frequencies, other prominent peaks also appear at very low frequencies showing the influence of wind on the response.

키워드

참고문헌

  1. Abou-rayan, A.M., Khalil, N.N. and Afify, M.S. (2016), "Dynamic behavior of TLP' s supporting 5 -M.W. wind turbines under multi-directional waves", Ocean Syst. Eng., 6(2), 203-216. https://doi.org/10.12989/ose.2016.6.2.203
  2. Ahmad, S., Islam, N. and Ali, A. (1997), "Wind-induced response of a tension leg platform", J. Wind Eng. Ind. Aerod., 72, 225-240. https://doi.org/10.1016/S0167-6105(97)00238-9.
  3. Bae, Y.H. and Kim, M.H. (2011), "Discussion on Rotor-floater-mooring coupled dynamic analysis of mono-column-TLP-type FOWT (Floating Offshore Wind Turbine)", Ocean Syst. Eng., 1(3), 243-248. https://doi.org/10.12989/ose.2011.1.3.243.
  4. Bithin, G., Selvam, R.P. and Sundaravadivelu, R. (2015), "Hydrodynamic Responses of a Single Hinged and Double Hinged Articulated Towers", Proceedings of the 34th Int. Conference on Ocean, Offshore and Arctic Engineering, May 31 - June 5, Newfoundland, Canada.
  5. Chakrabarti, S.K. (1971), "Discussion of Nondeterministic analysis of offshore structures", J. Eng. Mech. Division, 97(3), 1028-1029. https://doi.org/10.1061/JMCEA3.0001401
  6. Chakrabarti, S.K. (2005), Handbook of Offshore Engineering. Plainfield, IL: Elsevier.
  7. Chandrasekaran, S., Jain, A.K. and Chandak, N.R. (2007), "Response behavior of triangular tension leg platforms under regular waves using stokes nonlinear wave theory", J. Waterw., Port, Coast. Ocean Eng., 133(3), 230-237. https://doi.org/10.1061/(ASCE)0733-950X(2007)133:3(230).
  8. Chandrasekaran, S., Bhaskar, K., Lino, H. and Brijitrh, R. (2010), "Dynamic response behaviour of multi-legged articulated tower with and without TMD", Proceedings of the International Conference on Marine Technology.
  9. Chandrasekaran, S., Madhuri, S. and Jain, A.K. (2013), "Aerodynamic response of offshore triceratops", Ship. Offshore Struct., 8(2), 123-140. https://doi.org/10.1080/17445302.2012.691271.
  10. Chandrasekaran, Srinivasan, and Nannaware, M. (2014), "Response analyses of offshore triceratops to seismic activities", Ship. Offshore Struct., 9(6), 633-642. https://doi.org/10.1080/17445302.2013.843816.
  11. Chandrasekaran, Srinivasan, and Nassery, J. (2017), "Nonlinear response of stiffened triceratops under impact and non-impact waves", Ocean Syst. Eng., 7(3), 179-193. https://doi.org/10.12989/ose.2017.7.3.179.
  12. Chopra, A.K. (2003), Dynamics of Structures, 5th Ed., Pearson.
  13. El-gamal, A., Essa, A. and Ismail, A. (2014), "Influence of Tethers Tension Force on the response of Triangular Tension Leg Platform subjected to hydrodynamic waves", Proceedings of the International Conference on Civil and Architecture Engineering.
  14. Goda. (1970), Numerical experiments on wave statistics with spectral simulation. Japan.
  15. Hasan, S.D., Islam, N. and Moin, K. (2011), "Multihinged Articulated Offshore Tower under Vertical Ground Excitation", J. Struct. Eng. Eng., 137, 469-480. https://doi.org/10.1061/(ASCE)ST.1943-541X.0000284.
  16. Islam, A.B.M.S., Jameel, M., Ahmad, S. and Jumaat, Z. (2014), "Structural behaviour of fully coupled spar-mooring system under extreme wave loading", J. Civil Eng. Management, 19, S69-S77. https://doi.org/10.3846/13923730.2013.801899.
  17. Islam, N., Zaheer, M.M. and Ahmed, S. (2009a), "Double hinged articulated tower interaction with wind and waves", J. Wind Eng. Ind. Aerod., 97(5-6). https://doi.org/10.1016/j.jweia.2009.07.002.
  18. Islam, N., Zaheer, M.M. and Ahmed, S. (2009b), "Response of double hinged articulated tower platforms to wind forces", Wind Struct., 12(2), 103-120. https://doi.org/10.12989/was.2009.12.2.103
  19. Jain, A.K. and Chandrasekaran, S. (2004), "Aerodynamic behaviour of offshore triangular tension leg platforms", Proceedings of the ISOPE Conference, Toulon, France.
  20. Jain, A.K. and Datta, T.K. (1990), "Nonlinear response of guyed tower to random wave forces", Probab. Eng. Mech., 5(2), 66-75. https://doi.org/10.1016/0266-8920(90)90009-9.
  21. Kareem, A. (1983), "Nonlinear dynamic analysis of compliant offshore platforms subjected to fluctuating wind", J. Wind Eng. Ind. Aerod., 14(1-3), 345-356. https://doi.org/10.1016/0167-6105(83)90036-3.
  22. Kareem, A. (1985), "Wind-Induced Response Analysis of Tension Leg Platforms", J. Struct. Eng., 111(1), 37-55. https://doi.org/10.1061/(ASCE)0733-9445(1985)111:1(37)
  23. Karimirad, M. and Moan, T. (2012), "Wave- and Wind-Induced Dynamic Response of a Spar-Type Offshore Wind Turbine", J. Waterw., Port, Coast. Ocean Eng., 138, 9-20. https://doi.org/10.1061/(ASCE)WW.1943-5460
  24. Kim, H.C. and Kim, M.H. (2015), "Global performances of a semi-submersible 5MW wind-turbine including second-order wave-diffraction effects", Ocean Syst. Eng., 5(3), 139-160. https://doi.org/10.12989/ose.2015.5.3.139.
  25. Leonard, J.W. and Young, R.A. (1985), "Coupled response of compliant offshore platforms", Eng. Struct., 7(2), 74-84. https://doi.org/10.1016/0141-0296(85)90017-3.
  26. Malayjerdi, E. and Tabeshpour, M.R. (2016), "Frequency domain analysis of Froude-Krylov and diffraction forces on TLP", Ocean Syst. Eng., 6(3), 233-244. https://doi.org/10.12989/ose.2016.6.3.233.
  27. Moharrami, M. and Tootkaboni, M. (2014), "Reducing response of offshore platforms to wave loads using hydrodynamic buoyant mass dampers", Eng. Struct., 81, 162-174. https://doi.org/10.1016/j.engstruct.2014.09.037.
  28. Myrhaug, D. (2007), "Wind gust spectrum over waves: Effect of wave age", Ocean Eng., 34, 353-358. https://doi.org/10.1016/j.oceaneng.2006.01.003
  29. Nagavinothini, R. and Chandrasekaran, S. (2019), "Dynamic analyses of o ff shore triceratops in ultra-deep waters under wind, wave, and current", Structures, 20, 279-289. https://doi.org/10.1016/j.istruc.2019.04.009.
  30. Ostergaard, C. and Schellin, T.E. (1987), "Comparison of experimental and theoretical wave actions on floating and compliant offshore structures", Appl. Ocean Res., 9(4), 192-213. https://doi.org/10.1016/0141-1187(87)90002-2.
  31. Oyejobi, D.O., Jameel, M., Hafizah, N. and Sulong, R. (2016), "Stochastic Response of Intact and a Removed Tendon Tension Leg Platform to Random Wave and Current Forces", Arab J. Sci. Eng., https://doi.org/10.1007/s13369-016-2282-4.
  32. Philip, V., Joseph, A. and Joy, C.M. (2015), "Three Legged Articulated Support for 5 MW Offshore Wind Turbine", Aquatic Procedia, 4(Icwrcoe), 500-507. https://doi.org/10.1016/j.aqpro.2015.02.065.
  33. Rahman, M., Islam, A.B.M.S., Zamin, M. and Huda, N. (2017), "Response of nonlinear offshore spar platform under wave and current", Ocean Eng., 144, 296-304. https://doi.org/10.1016/j.oceaneng.2017.07.042.
  34. Saiful Islam, A.B.M. (2018), "Dynamic characteristics and fatigue damage prediction of FRP strengthened marine riser", Ocean Syst. Eng., 8(1), 21-32. https://doi.org/10.12989/ose.2018.8.1.021.
  35. Santo, H., Taylor, P.H., Bai, W. and Choo, Y.S. (2015), "Current blockage in a numerical wave tank : 3D simulations of regular waves and current through a porous tower", Comput. Fluid., 115, 256-269. https://doi.org/10.1016/j.compfluid.2015.04.005
  36. Simiu, E. and Stefan D.L. (1984), "Turbulent Wind and Tension Leg Platform Surge", J. Struct. Eng.- ASCE, 110(4), 785-802. https://doi.org/10.1061/(ASCE)0733-9445(1984)110:4(785)
  37. Sarpkaya, M. and Isasson, T. (1981), Mechanics of wave forces on offshore structures, 1st Ed. the University of California: Van Nostrand Reinhold Co.
  38. Wirsching, P.H. and Chen, Y.N. (1987), "Fatigue design criteria for TLP tendons", J. Struct. Eng.- ASCE, 113 (7), 1398-1414. https://doi.org/10.1061/(ASCE)0733-9445(1987)113:7(1398)
  39. Ye, K. and Ji, J. (2019), "Current , wave , wind and interaction induced dynamic response of a 5 MW spartype offshore direct-drive wind turbine", Eng. Struct., 178, 395-409. https://doi.org/10.1016/j.engstruct.2018.10.023.
  40. Zaheer, M.M. and Islam, N. (2008), "Aerodynamic response of articulated towers: state-of-the-art", Wind Struct., 11(2), 97-120. https://doi.org/10.12989/was.2008.11.2.097
  41. Zaheer, M.M. and Islam, N. (2009), "Fatigue and fracture reliability of articulated tower joint under random loading", Proceedings of the 28th Int. Conf on Ocean, Offshore and Arctic Engineering, Honolulu, Hawaii, USA, May 31-June 5, doi:10.1115/OMAE2009-79360.
  42. Zaheer, M.M. and Islam, N. (2010), "Reliability analysis of universal joint of a compliant platform", Fatigue Fract. Eng. Mater. Struct., 33(7), 408-419. https://doi.org/10.1111/j.1460-2695.2010.01453.x.
  43. Zaheer, M.M. and Islam, N. (2012), "Stochastic response of a double hinged articulated leg platform under wind and waves", J. Wind Eng. Ind. Aerod., 111, 53-60. https://doi.org/10.1016/j.jweia.2012.08.005.
  44. Zaheer, M.M. and Islam, N. (2017), "Dynamic response of articulated towers under correlated wind and waves", Ocean Eng., 132, 114-125. https://doi.org/10.1016/j.oceaneng.2017.01.019