中文摘要：

推导了桨叶的应变-位移关系,应用Hamiton原理建立了多路传力的无轴承旋翼桨叶运动的有限元方程,考虑了桨叶、柔性梁、扭矩套的位移协调条件和非线性变形耦合及摆振销的影响,并构造了一个新的15自由度梁单元,得到了旋翼桨叶固有频率求解的方程,重点研究了柔性梁刚度特性对旋翼桨叶固有频率的影响。数值结果表明：柔性梁剖面的模态刚度发生变化时,模态频率变化较小,高阶模态频率变化比低阶大,其它模态频率变化很小,耦合现象不明显。

英文摘要：

Strain-displacement relations of blades are presented.The finite element equtions of motion for bearingless rotor blades with lag pins modeled as mutipile load paths are derived from Hamilton＇s principle,which consider the effects of rotors deformation coupling.Certain displacement compatibility contions are satisfied at the junction where the main blade,flexbeam and torquwe tube joint and a new 15-DOF beam element is developed.The formulations to exam natural frequencies of blades are obtained.The effects of flexbeam stiffness properties on the dynamic specification of bearingless rotors are investigated.The results show that a mode frequency of the rotor changes slowly with the modal stiffness propertie of the flexbeam cross-section,the effects is great at the high order,coupling phenomenon is not obvious.