【摘要】 在非线性混合海况(风浪与涌浪的组合)下,以NREL 5MW导管架式近海风机为研究对象,预报导管架支撑结构泥线处受到的长期载荷。在时域仿真中,选用Ochi-Hubble六参数波浪谱,编制该谱的程序并将其嵌入到FAST中进行编译。在线性与非线性不规则波条件下的波高,泥线处的首尾向剪力和首尾向弯矩进行统计分析。采用分块最大值法提取短期载荷极值,使用广义极值分布进行拟合,极大似然估计法估计分布参数。经验分布与广义极值分布的拟合检验效果较好。计算结果表明,研究非线性混合海况下近海风机的导管架式支撑结构对工程实际更具有指导意义。更多还原

【Abstract】 Under the nonlinear mixed sea states(combination of wind waves and swells), the NREL 5 MW_Baseline Jacket offshore wind turbine is used as the research object to predict the long-term loads at the mudline of the jacket support structure. In the time-domain simulation, the Ochi-Hubble six-parameter wave spectrum is selected, and the program of the spectrum is developed and embedded into FAST for compilation. During the calculation, 20 simulations of 10 minutes are performed. For the short-term load obtained, we make a statistical analysis of the wave elevation and the fore-aft tower base shear and the fore-aft tower bending moment at the mudline under the influence of linear and nonlinear irregular waves. The block maximum method is used to extract the short-term load extreme value, and the generalized extreme value distribution is used for fitting. The maximum likelihood estimation method is used to estimate the parameters of the generalized extreme value distribution. The verification of fitting of the empirical distribution and the generalized extreme value distribution is good, and the long-term load is predicted based on the generalized extreme value distribution. The results show that the study of the jacket support structure of offshore wind turbines is more instructive for engineering practice under nonlinear mixed sea states.更多还原