柔性旋转带冠叶片的非线性动力学特征  

Nonlinear dynamical characteristics of a flexible rotating shrouded blade

作　　者：初世明[1] 曹登庆[1] 潘健智[1] 孙述鹏[1] 王立刚[2] 

机构地区：[1]哈尔滨工业大学航天学院,哈尔滨150001 [2]哈尔滨工程大学理学院,哈尔滨150001

出　　处：《中国科学：物理学、力学、天文学》2013年第4期424-435,共12页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：国家自然科学基金资助项目(批准号:11002037;50935002)

摘　　要：本文研究柔性旋转带冠叶片的接触振动问题.应用Frobenius方法计算旋转带冠叶片横向振动的动频和模态函数,并给出了模态函数正交性的证明.提出了利用叶片的弯曲动刚度描述的等效接触刚度来确定相邻旋转叶片接触刚度的方法,在此基础上,采用Galerkin截断将叶片的偏微分运动微分方程离散为常微分方程描述的旋转带冠叶片的分段线性动力系统.然后应用平均法,计算了旋转带冠叶片在尾流激励下的主共振响应,并分析当相邻叶冠间隙、尾流激励力幅值、叶片厚度和长度作为可调参数时系统的动力学响应与非线性行为,揭示了旋转带冠叶片的碰撞振动机理以及叶冠结构参数与叶片振动抑制之间的关系.The contact vibration problem of flexible rotating shrouded blades is studied in this paper. The Frobenius method is adopted to work out the transverse vibration modes of a rotating shrouded blade, and the orthogonality of modes is also proved. The contact stiffness of adjacent rotating blades is assumed to be the equivalent contact spring stiffness which is determined in terms of the bending dynamic stiffness of the blade. The Galerkin method is employed to discretize the partial governing differential equation of the rotating blade to a set of ordinary differential equations, in which the impact vibration process of the shrouded blade is described by a piecewise linear dynamical system. Then the average method is applied to obtain the primary resonant response of the system in the case of wake flow excitation. Taking the gap between adjacent blade shrouds, the amplitude of the external load, the width, thickness and length of the blade as adjustable parameters the nonlinear dynamical responses of the rotating blade are obtained and used to analyze the nonlinear behaviour of the system. In this way, the shock and vibration mechanism of the shrouded blade is revealed and the relationship between vibration suppression and structure parameters of the blade shroud is studied.

关 键 词：振动 柔性带冠叶片 碰撞 接触刚度 

分 类 号：TK14[动力工程及工程热物理—热能工程]