海上风力机浮式支撑结构平台系统耦合动力响应机理研究

The floating platform structures have critical influence on the safety of offshore wind power system, and inadequate understanding of structural coupling dynamics and kinematics seriously restrict their development in China. This project aims to numerically and experimentally study the structural coupling dynamics and kinematics as well as their mechanisms of floating offshore wind turbine supporting structures under the complex loads in ocean environment, and further to develop response prediction modelling, showing important academic significance and practical values. The main content of this project will include: analyzing the wind velocity database around a specified sea area to reveal the characteristic of offshore wind as well as to build the aerodynamic load model; investigating the interaction mechanism of wind and wave to build a prediction model for the wave growth from wind and the aerodynamics of the wind turbine to construct the aerodynamic loading model; constructing the nonlinear interaction model of mooring system to understand the mechanism of relaxation and breaking impact responses; developing an analytical method for the structural coupling dynamics and kinematics of floating offshore wind turbine supporting structures to build the governing equations for structures with nonlinear and large displacement; developing a high fidelity numerical solution method for the kinematics and coupling dynamics of structures to reveal the inherent mechanism under the complex ocean environment and the nonlinear characteristics and response mechanism of mooring system and finally to provide a theoretical and technical support for the optimization of the offshore floating wind power system.

浮式支撑结构平台对深海风电系统安全性具有关键作用，目前对其在复杂海况下的运动特性和耦合动力响应认识和规律掌握不足，制约了我国深海风电开发。本项目通过理论研究、数值计算和模型试验，研究海上风力机浮式支撑结构平台系统在海洋复杂环境荷载下的运动特性和耦合动力响应，建立响应预测模型。本研究即具有较深刻学术意义又有显著应用价值。内容包括：分析特定海域既有海洋风观测数据和工程相关特征，揭示近海面风作用特性，提出海洋风模拟方法；研究风浪耦联机制，建立风生浪预测模型；研究海上风机气动特性，建立其气动荷载模型；构建系泊非线性耦合力学模型，认识系泊松弛与破断冲击响应规律；提出浮式平台结构整体系统运动和耦合动力学模型的理论方法，建立耦合运动控制方程，构建结构运动和耦合动力高效求解方法，揭示复杂海况下结构运动特性和耦合动力效应机理、系泊非线性力学特性和响应机理，为海上浮式风电系统设计和安全性提供理论支撑。

海洋资源和海洋空间利用是我国的重要战略。海上浮式风力机是开发深海绿色风电资源的核心装备，浮式支撑结构平台是保障深海风电系统安全运行的关键。我国深海浮式风电系统研发起步不久，自主核心技术匮乏，对复杂海洋环境下的浮式支撑平台运动特性和耦合动力学响应机理的认识欠缺。本项目通过理论分析、数值计算和模型试验的技术路径，提出了V形叶片海上垂直轴风力机新体系，优化了达里厄型垂直轴风力机几何形体，构建了垂直风力机叶片/翼型的优化算法，提出了高性能叶片/翼型，显著提升了风力机的风电转化率，改善了体系结构气动特性；揭示了直线翼（两翼、三翼）H型垂直轴风机的空气动力学效应特性和尾流性态及其停机状态下的气动力特性，阐明了海风来流湍流强度对H型垂直轴风机风电转化效能和尾流场的影响规律；明晰了浮式平台纵摇或纵荡运动下的风力机系统风能转化效率、气动特性和尾流场特性及其演化规律；揭示了风浪作用下半潜式平台的结构动力学效应特性；发现了垂直轴风力机气动噪声特性规律及其机理；提出了基于混合深度学习模型的海洋短期风速预测方法；建立了风生浪耦合模型，阐明了海洋风-波耦联关系；提出了模拟钢材宏观与微观裂纹相互影响的多尺度扩展有限元改进方法，基于多尺度投射技术和扩展有限元法计算模拟，揭示了钢材微观初始缺陷与宏观裂纹的相互作用机制。结合项目组实际，扩展了研究内容，分析揭示了细长结构物（海洋立管、变截面长柱等）流体动力学效应特性及尾流场性态，圆柱尾流特性及其尾流控制；研究阐明了城镇区域雾霾颗粒扩散规律与机理。项目成果可为研发深海浮式风力机系统及其抗风浪安全性设计提供技术支撑。