海上浮式垂直轴风力机的气动特性研究

Study on the aerodynamic characteristics of offshore floating vertical axis wind turbine

海上垂直轴风力机受浮式基础运动的影响,气动载荷非常复杂,讨论浮式基础运动对风力机气动性能的影响尤为重要。本文分析叶片数量、翼型、形状和风轮实度对风机功率系数的影响,确定最佳风机结构参数;讨论塔柱与浮式基础运动对风机功率系数的影响。采用基于叶素动量理论的双致动盘多流管模型计算风机功率系数,运用CFD方法研究风机的气动特性,并与理论结果对比。结果表明:塔柱对风机功率的影响在大尖速比时更为明显;基础的垂荡运动会影响风机的功率系数,不同尖速比的影响结果不同;尖速比增大,不同垂荡周期的基础运动影响差别逐渐显现。

The aerodynamic load of offshore vertical-axis wind turbine with floating foundation is highly complicated. Therefore,the influence of the motion of a floating foundation on the aerodynamic performance of the wind turbine should be investigated. The effects of different numbers of blades,airfoils of blade section,rotor solidity,and shapes of blade on the power coefficient of the wind turbine were discussed. The optimum structural parameters of the wind turbine were also determined. The influence of tower and the motion of a floating foundation on the aerodynamic load of the wind turbine were analyzed. A double-multiple streamtube model,which is based on blade element momentum theory,was applied to calculate the power coefficient of the wind turbine. CFD method was applied to study the aerodynamic characteristics of the wind turbine,and the results were compared with the theoretical findings. The influence of tower on power was found to be more obvious at a high tip speed ratio. The heave motion of the foundation will affect the power coefficient of the wind turbine,and the influences at different tip speed ratios vary. When the tip speed ratio increases,the difference in effects of the foundation motion of various heave cycles is gradually revealed.