接触摩擦力对叶片减振能力的影响

在频域内利用谐波平衡法,分别通过理论分析和有限元分析方法对某涡轮叶片缘板-阻尼结构进行了减振效果分析,并就接触摩擦力对叶片减振能力的影响进行了进一步探索.研究发现带阻尼装置叶片由于阻尼块附加质量作用,对叶片有明显的避振作用,并也起到了一定的减振作用,但对叶片振动响应耗能影响最大的是叶片缘板-阻尼装置接触面的非线性摩擦力,且摩擦系数较小时叶片减振效果对其变化更敏感一些.另外从分析方法探索中发现,含接触等非线性问题的结构,忽略接触特性进行振动响应分析具有较大的偏差性.这些研究结论和研究方法可为阻尼结构的设计提供一定的参考.

Effect of Contact Friction on Blade Vibration Reduction

The vibration reduction effect of the turbine blade shroud damping structure was analyzed through theoretic analysis and finite element analysis,using harmonic balance method.And the vibration reduction effect of blades which influenced by contact friction was further explored.The research show that blade with a damper device because of the added mass effect of the damping has obvious vibration absorber and also play some damping effect.But the most energy dissipation on blade vibration response is the nonlinear contact fiction between the blade platform and the damping structure.And the vibration reduction effect of the blade is more sensitive when the friction coefficient is small.Also found from the analysis method,the response analysis of the contact nonlinear structure has a large deviation when ignore the contact characteristics.These research findings and research methods may provide some reference for the design of damping structure.