采用线性多步法和待定系数法建立一个新的三步三阶预估-校正时间步进法,用于自由涡尾迹方法离散涡线对流控制方程,该方法比现有差分格式更稳定,收敛更快。计算修正浮式平台运动对叶片入流和风轮尾迹形状的影响,建立了漂浮式风力机自由涡尾迹模型。采用该模型计算漂浮式风力机的气动性能,并与实验结果进行对比分析。研究结果表明,该模型能够准确地预估风力机稳态气动性能,并能准确地反映漂浮式平台运动对尾迹形状和气动性能的影响。
A new three-step and third-order predictor-corrector time-marching algorithm, for the difference of the wake governing equation in the free vortex wake method, is developed using the linear multistep method and the undetermined coefficient method. The present time-marching algorithm is found to produce a stabler and more quickly convergent wake system than the existing schemes. A free vortex wake model of the floating wind turbine, in which the blade inflow conditions and the positions of initial points of vortex filaments are modified, is developed. The comparison between calculation and experiment of a floating wind turbine aerodynamic performance is made. The results indicate that the developed model can predict the steady aerodynamic performance accurately and can consider the effect of the floating platform motions on the wake geometry and the aerodynamic performance.