考虑转速及碰摩的带冠涡轮叶片动力特性研究

Dynamic Characteristics of Flexible Shrouded Blades in Aero-engines

研究了考虑旋转及碰摩复合作用的带冠叶片振动特性。建立了模拟带冠涡轮叶片循环对称结构的梁-质量-弹簧模型;采用欧拉-贝努利梁理论,将系统放入转速引起的离心力场中,研究旋转状态下带冠叶片的动力特性;推导出了考虑离心力、气流激振力及碰摩复合作用的系统动力学方程;基于推导出的方程,研究了叶冠接触角、气流激振力、摩擦因数、刚度比和间隙等参数对系统稳态响应的影响规律。此外,还对系统的非线性特性进行了一定的研究。文中的分析方法及数值结果对于叶冠设计及振动控制有一定的参考价值。

The effect of impact and friction between shrouded blades in aero-engines under rotational speed is in-vestigated to analyze the influence of parameters of shrouded blade system on dynamic characteristics of the system . To investigate the impact and friction , a model composed of springs and a cantilever beam carrying a mass is devel-oped to simulate the cyclic symmetry structure of the shrouded blade in aero-engines .The model is placed into a centrifugal force field caused by a high rotational speed , and the centrifugal force is taken into account .The Euler-Bernoulli beam theory is employed to get the equation of motion by considering the centrifugal forces , the gas exci-tation forces and the combined effect of the impact and friction between shrouds .Based on the equation of motion , parametric analysis is performed to study the effect of the contact angle , the gas excitation force , the friction coeffi-cient, the stiffness and the gap between shrouds on the steady-state responses of the system .Numerical results and their analysis show preliminarily that the parameters have effects on the dynamic characteristics of the system .The results of the analysis are meaningful to the design of the shrouds and the control of the vibrations .