基于气动-水动-结构耦合模型的半潜风机动力响应分析

Dynamic Response Analysis of Semi-Submersible FOWT Based on Coupled Aero-Hydro-Structural Model

针对我国海洋环境条件,提出一种新型半潜式浮式基础,用于支撑5 MW海上风机。针对该新型浮式风机系统,采用叶素动量理论计算风轮所受气动载荷,采用三维势流理论计算基础水动力性能,分别采用杆单元和梁单元模型,基于有限元方法计算柔性体的动力响应。建立气动-水动-结构耦合的动力学分析模型,针对切入、额定和切出海况,在时域内计算风机的动力响应特性。计算结果表明:在不同作业海况下,新型半潜浮式风机基础运动性能良好,且系泊缆张力满足安全要求;风机叶片在风轮旋转平面外的变形显著大于风轮平面内的变形,且在额定海况下变形更大。

Based on the offshore environmental conditions in China,a new type of semi-submersible floating foundation is proposed to support 5 MW offshore wind turbine.Focusing on this new type of semi-submersible Floating Offshore Wind Turbine(FOWT)system,the aerodynamic loads on the rotor is calculated based on the blade element momentum theory.The hydrodynamic performance of the foundation is calculated based on the three dimensional potential theory.By adopting the bar model and beam model respectively,the dynamic responses of the flexible bodies are calculated based on the finite element method.The aero-hydro-structural coupling dynamic model is established.Considering the cut-in,rated and cut-off sea states,the dynamic responses of the FOWT is calculated in time domain.The results show that:the new-type of semi-submersible FOWT foundation is of good motion performance under different operational conditions,and the mooring tension meets the safety requirement;the blade tip deformations in the rotation plane are significantly larger than those out of the rotation plane,and the larger deformations are observed under the rated sea condition.