考虑应变依赖性特征的硬涂层整体叶盘非线性减振分析

Nonlinear vibration reduction analysis of hard-coating blisk with strain-dependent manner

为了提升整体叶盘在恶劣工况下的运行可靠性,提出一种对叶片附加非线性硬涂层材料的被动阻尼减振方法,并研究具有应变依赖性的涂层整体叶盘的非线性振动特性。首先,利用实验离散数据和高阶多项式描述具有应变依赖性的硬涂层材料的非线性力学参数;然后,利用改进的Oberst梁理论和基于正交多项式的Rayleigh-Ritz能量法建立涂层整体叶盘的非线性动力学模型;其次,提出基于Newton-Raphson法的非线性迭代求解流程,研究涂层整体叶盘的非线性振动特性;最后,选择叶片附加非线性NiCoCrAlY+YSZ硬涂层的整体叶盘为实例进行数值分析与实验测试。研究结果表明:在使整体叶盘固有频率变化不大的前提下,硬涂层可以有效抑制其振动响应峰值,而应变依赖性则进一步加强了硬涂层材料对整体叶盘的振动控制。

In order to improve the operating reliability of integrally bladed disk(blisk)under severe conditions,a novel methodology of passive vibration reduction by damping nonlinear hard-coating materials on blades was proposed,and the nonlinear vibration characteristics of hard-coating blisk were investigated.Firstly,based on the discrete values obtained from the vibration experiment,the nonlinear mechanical parameters of hard-coating material were characterized using high-order polynomials;the nonlinear dynamic model of hard-coating blisk was established using the modified Oberst beam theory and the energy-based Rayleigh-Ritz method considering orthogonal polynomials;next an iterative solution procedure based on the Newton-Raphson method was developed to solve the nonlinear vibration characteristics of hard-coating blisk.Finally,the numerical calculation of an academic blisk deposited nonlinear NiCoCrAlY+YSZ hard coating on both sides of blades was conducted,and the comparasions of numerical and experimental results were carried out for model validation.The results show that the vibration responses of the blisk are suppressed effectively by the hard-coating material without influencing its natural frequencies significantly,and these functions for vibration reduction can be further reduced by the strain-dependent manner.