基于拓扑与尺寸优化的风力机叶片轻量化设计

为有效减轻风力机叶片质量, 进一步实现降本增效, 对叶片内部结构进行拓扑优化与尺寸优化设计. 首先以叶片内部单元密度为设计变量, 将叶片柔顺度最小作为目标, 并以结构体积为约束条件, 考虑3种极限荷载工况, 利用ANSYS软件对叶片内部实体结构进行拓扑优化; 然后根据拓扑优化结果结合实际叶片内部材料铺层情况建立叶片壳体模型, 以关键结构参数为设计变量, 以叶片质量最轻为目标, 叶片强度、刚度、振动性能及稳定性等为约束, 采用MATLAB和ANSYS软件对叶片内部结构进行尺寸优化. 拓扑优化结果表明, 对叶片传统结构形式进行适当改进, 可有效改善叶片结构性能; 尺寸优化结果表明, 基于拓扑优化结果的改进结构优化方案与初始方案相比质量减轻了12.4%, 与传统结构优化方案相比质量减轻了2.6%, 较好地实现了叶片轻量化.

Lightweight design of wind turbine blade based on topology and size optimization

In order to reduce the mass of wind turbine blade effectively, and to further decrease cost and improve efficiency, topology optimization and size optimization design are conducted for the internal structure of the blade. Firstly, the topology optimization for the internal solid structure of the blade is carried out by using ANSYS with consideration of three ultimate load conditions, while employing the blade internal element densities as design variables, setting the minimum blade compliance as the objective, and taking the structure volume as the constraints. Then, a shell model of the blade is established according to the topology optimization result and the actual internal material lay-up. The size optimization for the internal structure of the blade is carried out by using both MATLAB and ANSYS to minimize the blade mass. The key structural parameters are used as the design variables, and strength, rigidity, vibration performance and stability are considered as the constraints. The topology optimization result shows that the blade structural performances can be effectively improved by modifying the conventional structure form of the blade appropriately. The size optimization result indicates that the optimization scheme of modified structure can reduce the mass by 12.4% when compared with the original scheme, and can further decrease the mass by 2.6% when compared with the conventional structure optimization result, which realizes the lightweight target of the blade well.