中文摘要：

采用笛卡尔坐标方法描述刚体运动,混合坐标系方法描述弹性体运动和变形,其中弹性变形由模态法表示。通过第一类Lagrange方程推出考虑气动弹性的刚柔混合多体系统的微分-代数方程组,其中代数方程为点和矢量的约束方程。采用Taylor预估、BDF（Backward Differential Formula）校正得到非线性方程组,继而采用Broyden算法求解,从而建立刚柔混合多体系统求解算法。对NH1500风力机进行多体动力学建模,其中机舱、轮毂简化为刚体,塔架、叶片为弹性体,在机舱与轮毂间施加驱动以模拟风力机的定速转动。结合自由涡尾迹的非定常气动力算法,实现考虑气动弹性的大型风力机整机多体动力学响应计算。分析了风剪切和弹性塔架对风力机气动弹性响应的影响,结果表明风剪切会使得叶片振动,而弹性塔架使得风力机响应增加。

英文摘要：

With the floating frame of reference used to represent the entire motion of the flexible bodies,in which the rigid body motion is represented by the motion of the floating frames and the elastic motion is represented by mode shapes,the governing equations of the multi-body system which considers aeroelastic effects are derived using the first class Lagrange equations,where the algebraic equations are composed of point and vector constraint equations derived from revolute joints and motion joints.The resulting differential-algebraic equations are transformed to algebraic equations using Taylor predictor and BDF（Backward differential formula）Corrector.The nonlinear algebraic equations are solved using Broyden method,then a multibody numerical method is established.The NH1500 wind turbine is built using the previous method,where the nacelle and hub are considered rigid,the blades and tower are considered flexible.A motion joint is added to represent the transmission chain between the nacelle and the hub.Unsteady aerodynamic loads are calculated by free vortex wake method.With the previous multi-body methods and free vortex wake method,the aeroelastic responses of the wind turbine system are numerically solved in time domain.The results show the wind shear effect leads to the vibration of the blade,and flexibility of the tower increases the responses of the blade.