直升机复合材料桨叶振动失效分析

Vibration Failure of Helicopter Composite Blade

针对某直升机复合材料旋翼桨叶,在没有对复杂结构进行简化的情况下,利用ANSYS有限元软件的参数化语言(APDL)建立完整的有限元模型。该模型不仅考虑了大梁、蒙皮和加强梁等主承力结构,还考虑了大梁内抗扭层、前缘包铁和前缘配重等次承力结构。利用该模型,计算桨叶在额定转速下的前5阶固有模态和频率。结果表明:前5阶模态不存在振动耦合,满足桨叶固有特性设计要求。在此基础上,计算不同转速下的各阶频率,绘出用于振动失效分析的坎贝尔图,经分析,在工作转速范围内,桨叶低阶固有频率没有与其旋转频率相交,满足固有频率设计要求。

Regarding a certain helicopter composite rotor blade,finite element method was used to create the integral model through APDL ANSYS without simplifying structure.Research not only about main structures like beam,skin,spar but substructures like inner twist wrap,nose crap,leading edge counter weight was considered in the model.Using this model,the first five natural vibration frequencies and modes of the blade were worked out.The results show that there is no vibrational coupling between the first five modes,and it satisfies the design demand.Based on this,the frequencies at different rotational speed as well as the Campbell diagram were worked out.No coupling occurs between low natural frequencies and rotational frequencies in the range of the rotational speed;the requirement of the design can be met.