半潜式海上浮式风力机平台随机响应特性分析

Stochastic response characteristics analysis of semisubmersible platform for floating offshore wind turbine

为了研究风力机平台的运动特性,利用风压模型模拟风力机气动载荷,基于势流理论和莫里森方程计算平台水动力,采用准静态悬链线理论模拟系泊系统,利用海洋工程工具SESAM软件建立了完整高效的风力机系统数值模型.针对自主设计的半潜式海上浮式风力机基础进行了水动力分析,数值分析结果与实验值符合较好.通过系统运动响应的统计数据和响应频谱研究了风力机气动载荷对风力机平台运动特性的影响.研究结果表明:该系统数值模型时效性较好,可真实反映浮式风力机平台的运动特性,风力机载荷在大幅增加平台的纵摇和纵荡响应的同时会对纵荡和系泊载荷频谱产生最直接的主导性影响.

In order to obtain the behavior of the platform for offshore wind turbine, the wind turbine was simplified as wind pressure model, the hydrodynamic load was calculated by potential theory and Morison equation, the mooring system was simulated using quasi-static catenary theory, and the whole numerical model was established though an ocean engineering software SESAM. For a designed semisubmersible platform, the hydrodynamic performance was analyzed and the numerical results fit well with the experiment. The impact of aerodynamic load on the platform behavior was studied through statistic data and response spectrums. It can be found that the wind pressure model can be used to simulate the wind turbine aerodynamic load, and the numerical model of the system is efficient and is able to reflect the behavior of the platform. The aerodynamic load significantly amplifies the pitch and surge responses and it dominants the surge and tension responses.