In this study, the coupled heave-pitch motion equations of a spar platform were established by considering lst-order and 2nd-order random wave loads and the effects of time-varying displacement volume and transient wa...In this study, the coupled heave-pitch motion equations of a spar platform were established by considering lst-order and 2nd-order random wave loads and the effects of time-varying displacement volume and transient wave elevation. We generated random wave loads based on frequency-domain wave load transfer functions and the Joint North Sea Wave Project （JONSWAP） wave spectrum, designed program codes to solve the motion equations, and then simulated the coupled heave-pitch motion responses of the platform in the time domain. We then calculated and compared the motion responses in different sea conditions and separately investigated the effects of 2nd-order random wave loads and transient wave elevation. The results show that the coupled heave-pitch motion responses of the platform are primarily dominated by wave height and the characteristic wave period, the latter of which has a greater impact. 2nd-order mean wave loads mainly affect the average heave value. The platform＇s pitch increases after the 2nd-order low frequency wave loads are taken into account. The platform＇s heave is underestimated if the transient wave elevation term in the motion equations is neglected.展开更多
针对现阶段随机冰力时域模拟方法单一的问题,将一种经典的时域模拟方法——快速傅里叶逆变换(Inverse Fast Fourier Transform,IFFT)法,引入海上风机单桩基础随机冰载荷研究中。结合随机冰力模型,采用MATLAB软件平台编写冰载荷时域模拟...针对现阶段随机冰力时域模拟方法单一的问题,将一种经典的时域模拟方法——快速傅里叶逆变换(Inverse Fast Fourier Transform,IFFT)法,引入海上风机单桩基础随机冰载荷研究中。结合随机冰力模型,采用MATLAB软件平台编写冰载荷时域模拟程序。基于山东省东营市渤中某海上风电场8.5 MW单桩式风机的结构与尺寸,进行算例分析,考虑入射角度作用,得到随机冰力在单桩基础结构上的实际分布情况,对IFFT法模拟随机冰力的精度和速度进行综合评价。结果表明,IFFT法作为一种计算简单快速、结果精确的时域模拟方法,适用于单桩基础随机冰力的计算,且所编程序可实现输入少量参数,快速高效获得冰力数值与分布的目的,具有实用性和推广性。展开更多
基金Foundation item： Supported by the National Natural Science Foundation of China under Grant No. 51279130 and No. 51239008
文摘In this study, the coupled heave-pitch motion equations of a spar platform were established by considering lst-order and 2nd-order random wave loads and the effects of time-varying displacement volume and transient wave elevation. We generated random wave loads based on frequency-domain wave load transfer functions and the Joint North Sea Wave Project （JONSWAP） wave spectrum, designed program codes to solve the motion equations, and then simulated the coupled heave-pitch motion responses of the platform in the time domain. We then calculated and compared the motion responses in different sea conditions and separately investigated the effects of 2nd-order random wave loads and transient wave elevation. The results show that the coupled heave-pitch motion responses of the platform are primarily dominated by wave height and the characteristic wave period, the latter of which has a greater impact. 2nd-order mean wave loads mainly affect the average heave value. The platform＇s pitch increases after the 2nd-order low frequency wave loads are taken into account. The platform＇s heave is underestimated if the transient wave elevation term in the motion equations is neglected.
文摘针对现阶段随机冰力时域模拟方法单一的问题,将一种经典的时域模拟方法——快速傅里叶逆变换(Inverse Fast Fourier Transform,IFFT)法,引入海上风机单桩基础随机冰载荷研究中。结合随机冰力模型,采用MATLAB软件平台编写冰载荷时域模拟程序。基于山东省东营市渤中某海上风电场8.5 MW单桩式风机的结构与尺寸,进行算例分析,考虑入射角度作用,得到随机冰力在单桩基础结构上的实际分布情况,对IFFT法模拟随机冰力的精度和速度进行综合评价。结果表明,IFFT法作为一种计算简单快速、结果精确的时域模拟方法,适用于单桩基础随机冰力的计算,且所编程序可实现输入少量参数,快速高效获得冰力数值与分布的目的,具有实用性和推广性。
