JOINT PROBABILITY DISTRIBUTION MODEL OF WIND AND WAVES FOR OFFSHORE WIND TURBINE IN JAPAN SEA AREA

Abstract

 In this study, we constructed a long-term joint probability distribution model of wind and waves using the observation data in offshore Kitakyushu city, for fatigue assessment of offshore wind turbine. However, it was found that the previous model underestimated the wind speed averaged wave period. Thus, the model was improved according to the wave characteristics in Japan Sea area. We proposed a model combining the developed wind-waves empirical model and the swell propagation model. It was confirmed that the improved model suppressed the excessive development of waves and reproduced the local wave characteristics well. In constructing the model, we proposed a new wave index, wave development coefficient, which quantified the development of wind waves.