基于等几何分析的风力机叶片PHT样条细分研究

Study on PHT Spline Refinement of Wind Turbine Blade Based on Isogeometric Analysis

等几何分析方法作为一种新型数值分析方法得到了广泛关注。针对传统等几何分析过程中,非均匀有理B样条(NURBS)曲线建模存在控制点较多、局部细化薄弱以及多面片拼接导致模型空间连续性较差等问题,提出一种基于PHT样条分层细分的等几何分析(IGA)方法。以某型风力机叶片为研究对象,分析了PHT样条细分对风力机叶片模型求解精度的影响,并通过有限元仿真结果进行对比分析。结果表明:细分前基于NURBS的风力机叶片模型等几何分析结果与有限元结果的相对误差为5.9%,细分后IGA结果与有限元结果的相对误差为3.7%,证明了经过PHT样条细分,风力机叶片的等几何分析求解精度得到了有效提高。提出的方法对后续风力机叶片的数值仿真和优化设计具有一定的参考意义。

Isogeometric analysis(IGA)has received widespread attention as a new numerical analysis method.Traditional NURBS curve modeling in geometric analysis suffers from problems,such as a large number of control points,weak local refinement,and poor model space continuity caused by multi-patch stitching.To address these issues,a PHT spline hierarchical subdivision-based IGA method is proposed and applied to study wind turbine blades.Taking a certain wind turbine blade as the research object,the influence of PHT spline refinement on the accuracy of wind turbine blade model solutions is analyzed,and the results are compared with finite element simulation results.The research results show that the relative error between the IGA result based on the NURBS wind turbine blade model before refinement and the finite element result is 5.9%;after PHT spline refinement,the relative error between the IGA result and the finite element result is reduced to 3.7%,which effectively improving the IGA solution's accuracy for wind turbine blades.The proposed method has important guiding significance for future wind turbine blades'numerical simulation and optimization design.