基于微动滑移模型的叶片阻尼结构参数研究

Study on Damping Structure Parameters of Blades Based on the Microslip Model

基于单边微动滑移的干摩擦阻尼模型,采用Timoshenko梁单元模化叶片,建立了带干摩擦阻尼结构叶片的动力学方程．针对该微分方程的非线性特点,采用一阶谐波平衡法,进行了动力响应的计算分析．研究了阻尼器的正压力、位置、截面拉伸刚度,以及激振力的位置和大小等阻尼结构参数对叶片系统响应的影响．研究结果表明:阻尼器的正压力和截面拉伸刚度存在一个最优值,使系统响应最小;阻尼器的位置对共振频率有较大的影响;激振力的大小和位置同样影响系统的动力特性．研究结果为叶片的最佳阻尼结构设计提供理论依据．

Equations of motion for damped blades were established using the finite element method, in which the friction dampers of blades were regarded as a microslip model and the blade structures was modeled with the Timoshenko beam. The harmonic balance method （HBM） was employed to solve the forced response of damped blades considering nonlinear feature of differential equations. Influence of parameters of damping structures such as normal force, location and tensile stiffness of the damper, location and magnitude of excitation force, on forced response of blades was studied. The calculated results show that the optimal normal force and tension stiffness exist for the system with the least forced response. Moreover, the location of the damper has a big effect on the resonance frequency of the system, and the location and magnitude of the excitation force also affect the dynamic characteristics of the system.