几种压电网络用于叶盘结构减振的机理分析

针对几种有望用于叶盘结构等循环对称结构减振的压电网络技术开展机理研究。为说明能量耗散及能量平衡两种不同的机理对减振、抑振效果的影响,基于集总参数模型对带有分支、并联网络、串联网络3类电路的叶盘结构开展了数值研究。对比了3类电路在谐调和失谐叶盘上所能达到的最佳减振效果及其随着失谐强度变化的规律,展示压电网络中能量耗散机理的作用。在非周期压电网络中加入了电阻,讨论了两种机理的共同作用。还给出了非周期压电网络最佳连接方式选择的定性建议。研究发现:将所有压电片连接到同一个网络并不能显著增加阻尼性能。在失谐叶盘上找到了无任何电路元件且只含少量叶片的非周期压电网络的最佳连接形式,说明了能量分配机理的作用。可以做到只将少数叶片连入网络(例如24个叶片中的2个或4个),无需加入任何电路元件就可以达到降低失谐响应放大效应的作用。

Analysis on mechanism of several piezoelectric networks for vibration reduction of bladed disks

The mechanisms of piezoelectric networks were further analyzed for the vibration reduction of cyclic periodic structures such as bladed disks. To illustrate how the energy dissipation and energy balance mechanisms affect the reduction of vibration, numerical studies were conducted based on a lumped parameter model to compare the performance of shunt circuits, parallel network and series network. The best damping performance of such three circuits were compared in both tuned and mistuned cases with varied mistune strength. This illustrated the effects of the energy dissipation. The resistance was introduced to the acyclic network to illustrate the combined action of energy balance and energy dissipation. The qualitative suggestions on the choice of blades to construct an acyclic network was given as well. Results showed that interconnecting all blades to a global piezoelectric network cannot increase the damping performance. The optimal networks were found with only few blades included and without any electric impedance, and this illustrated the effects of energy balance. Vibration reduction can be achieved by only interconnecting few blades (2 or 4 of the overall 24 blades) into the network without any electric components.