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Research Papers: Ocean Renewable Energy

Methodology for Assessment of the Allowable Sea States During Installation of an Offshore Wind Turbine Transition Piece Structure Onto a Monopile Foundation

[+] Author and Article Information
Wilson Guachamin Acero

Department of Marine Technology,
Centre for Ships and Ocean Structures (CeSOS),
Centre for Autonomous Marine Operations
and Systems (AMOS),
Norwegian University of Science
and Technology (NTNU),
Trondheim NO-7491, Norway;
Departamento de Ingeniería Mecánica,
Escuela Politécnica Nacional (EPN),
Quito 17-01-2759, Ecuador
e-mails: wilson.i.g.acero@ntnu.no,
wilson.guachamin@epn.edu.ec

Zhen Gao

Department of Marine Technology,
Centre for Ships and Ocean Structures (CeSOS),
Centre for Autonomous Marine Operations
and Systems (AMOS),
Norwegian University of Science
and Technology (NTNU),
Trondheim NO-7491, Norway

Torgeir Moan

Department of Marine Technology,
Centre for Ships and Ocean Structures (CeSOS),
Centre for Autonomous Marine Operations
and Systems (AMOS),
Norwegian University of Science and
Technology (NTNU),
Trondheim NO-7491, Norway

1Corresponding author.

Contributed by the Ocean, Offshore, and Arctic Engineering Division of ASME for publication in the JOURNAL OF OFFSHORE MECHANICS AND ARCTIC ENGINEERING. Manuscript received April 9, 2016; final manuscript received June 21, 2017; published online August 8, 2017. Assoc. Editor: Qing Xiao.

J. Offshore Mech. Arct. Eng 139(6), 061901 (Aug 08, 2017) (16 pages) Paper No: OMAE-16-1039; doi: 10.1115/1.4037174 History: Received April 09, 2016; Revised June 21, 2017

In this paper, a methodology suitable for assessing the allowable sea states for installation of a transition piece (TP) onto a monopile (MP) foundation with focus on the docking operation is proposed. The TP installation procedure together with numerical analyses is used to identify critical and restricting events and their corresponding limiting parameters. For critical installation phases, existing numerical solutions based on frequency and time domain (TD) analyses of stationary processes are combined to quickly assess characteristic values of dynamic responses of limiting parameters for any given sea state. These results are compared against (nonlinear and nonstationary) time domain simulations of the actual docking operations. It is found that a critical event is the structural damage of the TP's bracket supports due to the potential large impact forces or velocities, and a restricting installation event (not critical) is the unsuccessful mating operation due to large horizontal motions of the TP bottom. By comparing characteristic values of dynamic responses with their allowable limits, the allowable sea states are established. Contact–impact problems are addressed in terms of assumed allowable impact velocities of the colliding objects. A possible automatic motion compensation system and human actions are not modeled. This methodology can also be used in connection with other mating operations such as float-over and topside installation.

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References

Thomsen, K. E. , 2014, Offshore Wind—A Comprehensive Guide to Successful Offshore Wind Farm Installation, Elsevier, London, Chap. 5.
DNV, 2014, “ Offshore Standard DNV-OS-H205, Lifting Operations,” Det Norske Veritas, Oslo, Norway.
Clauss, G. , and Riekert, T. , 1990, “ Operational Limitations of Offshore Crane Vessels,” Offshore Technology Conference (OTC), Houston, TX, May 7–10, SPE Paper No. OTC-6217-MS. https://doi.org/10.4043/6217-MS
Nojiri, N. , and Sasaki, T. , 1983, “ Motion Characteristics of Crane Vessels in Lifting Operations,” Offshore Technology Conference (OTC), Houston, TX, May 2–5, SPE Paper No. OTC-4603-MS. https://doi.org/10.4043/4603-MS
Cozijn, J. , van der Wal, R. , and Dunlop, C. , 2008, “ Model Testing and Complex Numerical Simulations for Offshore Installation,” 18th International Offshore and Polar Engineering Conference, Vancouver, BC, Canada, July 6–11, SPE Paper No. ISOPE-I-08-080. https://www.onepetro.org/conference-paper/ISOPE-I-08-080
Jung, J. J. , Lee, W. S. , Shin, H. S. , and Kim, Y. , 2009, “ Evaluating the Impact Load on the Offshore Platform During Float-Over Topside Installation,” 19th International Offshore and Polar Engineering Conference, Osaka, Japan, June 21–26, SPE Paper No. ISOPE-I-09-330. https://www.onepetro.org/conference-paper/ISOPE-I-09-330
He, M. , Yuan, R. , Li, H. , Yu, W. , Qian, J. , and Wang, A. M. , 2011, “ Floatover Installation Analysis and Its Application in Boahi Bay,” 21st International Offshore and Polar Engineering Conference, Maui, HI, June 19–24, SPE Paper No. ISOPE-I-11-292. https://www.onepetro.org/conference-paper/ISOPE-I-11-292
Peace, D. , Tuturea, D. , Ellis, N. , and Chivvis, J. , 1985, “ Dynamic Analysis of the Hutton TLP Mating Operation,” Offshore Technology Conference (OTC), Houston, TX, May 6–9, SPE Paper No. OTC-5048-MS. https://doi.org/10.4043/5048-MS
Hamilton, J. , French, R. , and Rawstron, P. , 2008, “ Topsides and Jackets Modeling for Floatover Installation Design,” Offshore Technology Conference (OTC), Houston, TX, May 5–8, SPE Paper No. OTC-19227-MS. https://doi.org/10.4043/19227-MS
Guachamin Acero, W. , Li, L. , Gao, Z. , and Moan, T. , 2016, “ Methodology for Assessment of the Operational Limits and Operability of Marine Operations,” Ocean Eng., 125, pp. 308–327. [CrossRef]
Li, L. , Guachamin Acero, W. , Gao, Z. , and Moan, T. , 2016, “ Assessment of Allowable Sea States During Installation of OWT Monopiles With Shallow Penetration in the Seabed,” ASME J. Offshore Mech. Arct. Eng., 138(4), p. 041902. [CrossRef]
Guachamin Acero, W. , Gao, Z. , and Moan, T. , 2016, “ Assessment of the Dynamic Responses and Allowable Sea States for a Novel Offshore Wind Turbine Installation Concept Based on the Inverted Pendulum Principle,” Energy Procedia, 94, pp. 61–71. [CrossRef]
Guachamin Acero, W. , Gao, Z. , and Moan, T. , 2017, “ Numerical Study of a Novel Procedure for Installing the Tower and Rotor Nacelle Assembly of Offshore Wind Turbines Based on the Inverted Pendulum Principle,” J. Marine Sci. Appl., (in press).
Guachamin Acero, W. , Moan, T. , and Gao, Z. , 2015, “ Steady State Motion Analysis of an Offshore Wind Turbine Transition Piece During Installation Based on Outcrossing of the Motion Limit State,” ASME Paper No. OMAE2015-41142.
ISO, 2015, “ Ships and Marine Technology—Offshore Wind Energy-Port and Marine Operations,” International Organization for Standardization, Geneva, Switzerland, Standard No. ISO 29400. https://www.iso.org/standard/60906.html
Century Dynamics-Ansys, 2011, “ AQWA Reference Manual Version 14.0,” Century Dynamics-Ansys, Inc., Horsham, UK.
Lankhorst, 2015, “ Offshore Steel Wire Ropes,” Royal Lankhorst Euronete, Sneek, The Netherlands, accessed Nov. 29, 2015, http://www.lankhorstropes.com/files/uploads/Offshore/brochures/Steel_Wire_Rope_brochure__100dpi__April_2013.pdf
Jung, S. , Kim, S. R. , Patil, A. , and Hung, L. C. , 2015, “ Effect of Monopile Foundation Modeling on the Structural Response of a 5-MW Offshore Wind Turbine Tower,” Ocean Eng., 109, pp. 479–488. [CrossRef]
Hoit, M. , Chung, J. H. , Wasman, S. J. , and Bollmann, H. T. , 2007, “ Development of API Soil Models for Studying Soil-Pile Interaction Analysis Using FB-MultiPier,” Bridge Software Institute, University of Florida, Gainesville, FL.
API, 2000, “ Recommended Practice for Planning, Designing and Constructing Fixed Offshore Platforms-Working Stress Design,” American Petroleum Institute, Washington, DC, Standard No. API-RP-2A-WSD. http://latorebondeng90245.tripod.com/api_rp2a.pdf
Fylling, I. , 1994, “ On the Statistics of Impact Velocities and Hit Positions Related to Collisions and Mating Operations for Offshore Structures,” BOSS'94, Behaviour of Offshore Structures, C. Chryssostomidis , M. S. Triantafyllow , A. J. Whittle , and M. S. Hoo Fatt , eds., Elsevier, Boston, MA, Vol. 3, pp. 297–306.
Sandvik, P. C. , 2012, “ Estimation of Extreme Response From Operations Involving Transients,” Second Marine Operations Specialty Symposium (MOSS), Singapore, Aug. 6–8, pp. 103–112.
Low, Y. M. , 2009, “ Efficient Vector Outcrossing Analysis of the Excursion of a Moored Vessel,” Probab. Eng. Mech., 24(4), pp. 565–576. [CrossRef]
DNV, 2010, “ Environmental Conditions and Environmental Loads,” Det Norske Veritas, Oslo, Norway, Recommended Practice DNV-RP-C205.
DNV, 2011, “ Modelling and Analysis of Marine Operations,” Det Norske Veritas, Oslo, Norway, Recommended Practice DNV-RP-H103.
Hamilton, J. , and Ramzan, F. , 1991, “ Dynamic Analysis of Offshore Heavy Lifts,” The First International Offshore and Polar Engineering Conference, Edinburgh, UK, Aug. 11–16, Vol. 1, SPE Paper No. ISOPE-I-91-004. https://www.onepetro.org/conference-paper/ISOPE-I-91-004

Figures

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Fig. 1

Monopile and transition piece structures in the motion monitoring phase prior to mating [14]

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Fig. 2

Models for TP-MP axial contact–impact prior to mating: (a) physical model, (b) contact scenarios, and (c) spring–damper model

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Fig. 3

Lateral contact during TP mating operation: (a) physical model and (b) spring–damper model

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Fig. 4

Contact–impact during TP landing: (a) physical model and (b) spring–damper model

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Fig. 5

Potential critical events, limiting parameters, and allowable limits for the docking operation of a TP onto a MP foundation (refer to Fig. 1)

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Fig. 6

Dynamic coupled model for TP docking operation in the motion monitoring phase prior to mating

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Fig. 7

Methodology for assessment of the allowable sea states for the docking operation of a TP onto a MP foundation: (a) screening of limiting parameter and (b) assessment of allowable sea states

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Fig. 8

Numerical methods for assessment of dynamic responses

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Fig. 9

Determination of impact and snap velocities based on TP's bottom tip displacement and velocity TD histories: (a) TP's bottom tip relative heave displacements (with respect to the crane tip) for constant lowering speed and (b) possible impact and snap velocities (no winch speed included)

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Fig. 10

Allowable limits of sea states for the monitoring phase of the TP's bottom tip. Limiting parameter: TP's bottom tip motions, allowable crossing rate limit: νallow+=0.0167 Hz, and mating gap: r = 0.3 m. Wave direction measured counter clockwise from the HLV's stern.

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Fig. 11

Average number of crossings per minute based on stationary process TD simulations for various mating gaps

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Fig. 12

Statistical parameters of the axial impact velocities prior to the mating phase, based on the collision approach method

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Fig. 13

Dynamic responses as consequence of axial impact events vdyn = 0.10 m/s, vwinch = 0.033 m/s, ξa = 1.0 m, T = 7.0 s, and α = 135 deg. For the contact points, refer to Fig. 4(b).

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Fig. 14

Crossing rates and statistical parameters of radial impact velocities for r = 0.3 m, α = 135 deg: (a) number of crossing per minute and (b)–(d) statistical parameters averaged from several 5 min interval TD simulations

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Fig. 15

Statistical parameters for snap velocities during landing and lift-off, α = 135 deg. Statistical parameters averaged over several 5 min TD history intervals.

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Fig. 16

Allowable limits of sea states for TP-MP mating. Limiting parameter for the motion monitoring phase: crossing rate νallow+=0.0167 Hz for r = (0.3, 0.5) m, limiting parameter for the landing phase: vimp = (0.10, 0.18) m/s.

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Fig. 17

Statistical parameters of dynamic responses obtained from nonstationary process TD simulations of the TP lowering and landing operations for various sea states, 36 seeds, α = 135 deg

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Fig. 18

Example of dynamic responses from TD simulations of the lowering and landing phases. Hs = 1.60 m, Tp = 6 s, α = 135 deg.

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Fig. 19

Typical dynamic responses following impact events. ξa = 0.5 m, T = 7 s, α = 135 deg.

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