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Research Papers: Ocean Renewable Energy

The Effect of Environmental Contour Selection on Expected Wave Energy Converter Response

[+] Author and Article Information
Samuel J. Edwards

Naval Architecture and Marine
Engineering Department,
University of Michigan,
Ann Arbor, MI 48109
e-mail: sjedw@umich.edu

Ryan G. Coe

Sandia National Laboratories,
Water Power Technologies Department,
Albuquerque, NM 87185
e-mail: rcoe@sandia.gov

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 September 13, 2017; final manuscript received July 6, 2018; published online August 13, 2018. Assoc. Editor: Qing Xiao.The United States Government retains, and by accepting the article for publication, the publisher acknowledges that the United States Government retains, a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this work, or allow others to do so, for United States Government purposes.

J. Offshore Mech. Arct. Eng 141(1), 011901 (Aug 13, 2018) (7 pages) Paper No: OMAE-17-1165; doi: 10.1115/1.4040834 History: Received September 13, 2017; Revised July 06, 2018

A wave energy converter must be designed to both maximize power production and to ensure survivability, which requires the prediction of future sea states. It follows that precision in the prediction of those sea states should be important in determining a final WEC design. One common method used to estimate extreme conditions employs environmental contours of extreme conditions. This report compares five environmental contour methods and their repercussions on the response analysis of Reference Model 3 (RM3). The most extreme power take-off (PTO) force is predicted for the RM3 via each contour and compared to identify the potential difference in WEC response due to contour selection. The analysis provides insight into the relative performance of each of the contour methods and demonstrates the importance of an environmental contour in predicting extreme response. Ideally, over-predictions should be avoided, as they can add to device cost. At the same time, any “exceedances,” that is to say sea states that exceed predictions of the contour, should be avoided so that the device does not fail. For the extreme PTO force response studied here, relatively little sensitivity to the contour method is shown due to the collocation of the device's resonance with a region of agreement between the contours. However, looking at the level of observed exceedances for each contour may still give a higher level of confidence to some methods.

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References

Coe, R. , Neary, V. , Lawson, M. , Yu, Y. , and Weber, J. , 2014, “Extreme Conditions Modeling Workshop Report,” Sandia National Laboratories and National Renewable Energy Laboratory, Technical Report Nos. NREL/TP-5000-62305, SNL/SAND2014-16384R.
IEC, 2016, “Marine Energy—Wave, Tidal and Other Water Current Converters—Part 2: Design Requirements for Marine Energy Systems,” International Electrotechnical Commission, Geneva, Switzerland, Standard No. TS 62600-2:2016. https://webstore.iec.ch/publication/25634
Coe, R. G. , Yu, Y.-H. , and van Rij, J. , 2018, “A Survey of WEC Reliability, Survival and Design Practices,” Energies, 11(1), p. 4. [CrossRef]
Eckert-Gallup, A. , Sallaberry, C. J. , Dallman, A. R. , and Neary, V. S. , 2016, “Application of Principal Component Analysis (PCA) and Improved Joint Probability Distributions to the Inverse First-Order Reliability Method (I-FORM) for Predicting Extreme Sea States,” Ocean Eng., 112, pp. 307–319. [CrossRef]
Montes-Iturrizaga, R. , and Heredia-Zavoni, E. , 2015, “Environmental Contours Using Copulas,” Appl. Ocean Res., 52, pp. 125–139.
Kleiven, G. , and Haver, S. , 2004, “Met-Ocean Contour Lines for Design; Correction for Omitted Variability in the Response Process,” 14th International Offshore and Polar Engineering Conference, Toulon, France, May 23–28, Paper No. ISOPE-I-04-313. https://www.onepetro.org/conference-paper/ISOPE-I-04-313
Muliawan, M. J. , Gao, Z. , and Moan, T. , 2013, “Application of the Contour Line Method for Estimating Extreme Responses in the Mooring Lines of a Two-Body Floating Wave Energy Converter,” ASME J. Offshore Mech. Arct. Eng., 135(3), pp. 1–10.
Ren, N. , Gao, Z. , Moan, T. , and Wan, L. , 2015, “Long-Term Performance Estimation of the Spar-Torus-Combination (STC) System With Different Survival Modes,” Ocean Eng., 108, pp. 716–728. [CrossRef]
Child, B. , Oberhagemann, J. , Hann, M. , Greaves, D. , and Raby, A. , 2017, “A Methodology for Identification and Simulation of Extreme Design Load Cases for Wave Energy Converters,” Proceedings of the 5th Marine Energy Techonology Symposium (METS2017), Washington, DC, May 1–7.
Neary,V. S. , Previsic, M. , Jepsen, R. A. , Lawson, M. J. , Yu, Y-. H. , Copping, A. E. , Fontaine, A. A. , Hallett, K. C. , and Murray, D. K. , 2014, “Methodology for Design and Economic Analysis of Marine Energy Conversion (MEC) Technologies,” Sandia National Laboratories, Albuquerque, NM, Technical Report No. SAND2014-9040. http://energy.sandia.gov/wp-content/gallery/uploads/SAND2014-9040-RMP-REPORT.pdf
Coe, R. G. , Michelen, C. , Eckert-Gallup, A. C. , Yu, Y.-H. , and van Rij, J. , 2016, “A Toolbox for Extreme Response and Fatigue Analysis of WECs,” Proceedings of the Marine Energy Technology Symposium (METS2014), Capital Hilton, Washington, DC, Apr. 25–27.
Yu, Y. , Ruehl, K. , and Michelen, C. , 2014, “Development and Demonstration of the WEC-Sim Wave Energy Converter Simulation Tool,” Second Marine Energy Technology Symposium, Seattle, WA, Apr. 15–18.
Hall, M. , and Goupee, A. , 2015, “Validation of a Lumped-Mass Mooring Line Model With Deepcwind Semisubmersible Model Test Data,” Ocean Eng., 104, pp. 590–603. [CrossRef]
Falnes, J. , 1999, “Wave-Energy Conversion Through Relative Motion Between Two Single-Mode Oscillating Bodies,” ASME J. Offshore Mech. Arct. Eng., 121(1), pp. 32–38.
Coe, R. G. , and Neary, V. S. , 2014, “Review of Methods for Modeling Wave Energy Converter Survival in Extreme Sea States,” Second Marine Energy Technology Symposium (METS2014), Seattle, WA, Apr. 15–17.
Chatfield, C. , 2003, The Analysis of Time Series: An Introduction, Chapman and Hall/CRC, Boca Raton, FL.
Crandall, S. H. , and Mark, W. D. , 1963, Random Vibrations in Mechanical Systems, Academic Press, New York.
Lloyd, A. R. J. M. , 1998, Seakeeping: Ship Behaviour in Rough Weather, A R J M Lloyd, Chichester, England.
Newman, J. N. , 1978, Marine Hydrodynamics, MIT Press, Cambridge, MA.
Michelen, C. , and Coe, R. , 2015, “Comparison of Methods for Estimating Short-Term Extreme Response of Wave Energy Converters,” OCEANS 2015 - MTS/IEEE Washington, Washington, DC, Oct. 19–22.
Coles, S. , 2001, An Introduction to Statistical Modeling of Extreme Values, Springer, London; New York.
Naess, A. , and Moan, T. , 2013, Stochastic Dynamics of Marine Structures, Cambridge University Press, New York.

Figures

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Fig. 1

All contours with data from NDBC Buoy 46022 as well as energy period choices for analysis

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Fig. 2

Spectral density function for the PTO force time series from the PCA contour method with an energy period of 12.76 s

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Fig. 3

Extreme PTO force response for each contour method at given energy periods

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Fig. 4

Relationship between significant wave height and PTO force

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Fig. 5

Power take-off extreme response prediction coefficient of variation amongst contour methods for a range of sea state energy periods

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