This research provides a thorough investigation on aspects of the structural integrity of composite blades for a range of operating conditions using fluid-structure interaction analysis based on Computational Fluid dynamics (CFD) and Finite Element Method (FEM). Both shell elements and layered solid elements were used in the finite element model. The strength was assessed against Tsai-Wu, Hashin, and Hoffman criteria. The blade is subjected to combined loads of bend and twist that varying in magnitude, direction, and acting point therefore, the critical failure mode is shown to be highly affected by operating conditions which necessitates evaluating the strength for the whole operating range. The safe operating range was analyzed according to a guidance note recently released by Bureau Veritas (BV) which defines safety limits for individual and combined stresses across each ply. Interlaminar normal stress failure is shown to be the most critical mode of failure, hence a solid model is recommended over the shell model. The blade strength meets the requirement of BV rules when assessed by Hoffman criteria however, other failure criteria show insufficient strength at the design condition.

本研究使用基于计算流体动力学 (CFD) 和有限元方法 (FEM) 的流固耦合分析，对复合材料叶片在一系列操作条件下的结构完整性方面进行了彻底调查。有限元模型中同时使用了壳单元和分层实体单元。根据 Tsai-Wu、Hashin 和 Hoffman 标准评估强度。叶片承受弯曲和扭曲的组合载荷，这些载荷的大小、方向和作用点都不同，因此，临界失效模式受运行条件的影响很大，因此需要评估整个运行范围的强度。安全操作范围是根据 Bureau Veritas (BV) 最近发布的指导说明进行分析的，该指导说明定义了每个层的单个和组合应力的安全限制。层间正应力失效被证明是最关键的失效模式，因此建议使用实体模型而不是壳模型。通过霍夫曼准则评估叶片强度满足 BV 规则的要求，但其他失效准则在设计条件下显示强度不足。