Full long-term design response analysis of a wave energy converter

Efficient design of wave energy converters requires an accurate understanding of expected loads and responses during the deployment lifetime of a device. A study has been conducted to better understand best-practices for prediction of design responses in a wave energy converter. A case-study was performed in which a simplified wave energy converter was analyzed to predict several important device design responses. The application and performance of a full long-term analysis, in which numerical simulations were used to predict the device response for a large number of distinct sea states, was studied. Environmental characterization and selection of sea states for this analysis at the intended deployment site were performed using principle-components analysis. The full long-term analysis applied here was shown to be stable when implemented with a relatively low number of sea states and convergent with an increasing number of sea states. As the number of sea states utilized in the analysis was increased, predicted response levels did not change appreciably. However, uncertainty in the response levels was reduced as more sea states were utilized.

[1]  António F.O. Falcão,et al.  Wave energy utilization: A review of the technologies , 2010 .

[2]  J. Falnes Ocean Waves and Oscillating Systems , 2002 .

[3]  Torgeir Moan,et al.  Application of the Contour Line Method for Estimating Extreme Responses in the Mooring Lines of a Two-Body Floating Wave Energy Converter , 2013 .

[4]  C. Sallaberry,et al.  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 , 2016 .

[5]  Armin W. Troesch,et al.  Statistical Estimation of Extreme Roll in Head Seas , 2014 .

[6]  Carlos Michelen,et al.  Comparison of methods for estimating short-term extreme response of wave energy converters , 2015, OCEANS 2015 - MTS/IEEE Washington.

[7]  John V. Ringwood,et al.  Coordinated Control of Arrays of Wave Energy Devices—Benefits Over Independent Control , 2013, IEEE Transactions on Sustainable Energy.

[8]  Tristan Perez,et al.  Time- vs. frequency-domain identification of parametric radiation force models for marine structures at zero speed , 2008 .

[9]  Torgeir Moan,et al.  Numerical and experimental investigations into the application of response conditioned waves for long-term nonlinear analyses , 2009 .

[10]  Lance Manuel,et al.  Long-term loads for a monopile-supported offshore wind turbine , 2014 .

[11]  Marcos Queija de Siqueira,et al.  A coupled approach for dynamic analysis of CALM systems , 2002 .

[12]  Torgeir Moan,et al.  Long-term performance estimation of the Spar–Torus-Combination (STC) system with different survival modes , 2015 .

[13]  Ole David Økland,et al.  Combining contours of significant wave height and peak period with platform response distributions for predicting design response , 2010 .

[14]  Sverre Haver,et al.  Long Term Response Analysis of Fixed and Floating Structures , 1998 .

[15]  Ryan G. Coe,et al.  REVIEW OF METHODS FOR MODELING WAVE ENERGY CONVERTER SURVIVAL IN EXTREME SEA STATES , 2014 .