Session: 29-01 Active Controls of Rotordynamic Systems

Paper Number: 81683

81683 - Feasibility Analysis of the Rotor Elastic Support With Piezoelectric Damping 

As a typical support structure, squirrel-cage elastic support is widely used in aero-engines.  The combination of the squirrel-cage elastic support and damping structures, such as squeeze film dampers, can effectively suppress rotor vibration. The squeeze film damper, although providing significant damping, requires a specific auxiliary lubricant supply system, which occupies additional space and brings additional weight. Piezoelectric materials have the advantages of light weight, high energy density, and wide bandwidth. The electromechanical coupling effect ensures that they can be used as energy transducers. As a new damping technology, piezoelectric damping has attracted extensive attention in the field of structural vibration control, but mostly limited to the mechanism level through simple structures. In this study, two promising piezoelectric damping technologies, the shunted resonant damping and the synchronized switch damping (SSD), are integrated to the elastic support, respectively. Although the above-mentioned elastic support with piezoelectric damping can reduce additional mass and save space, its performance concerning the vibration suppression effect for the rotor needs to be verified. To do that, the finite element model of a dummy rotor with elastic support-piezoelectric damper system is established first. The spatial distribution and the interconnection mode of electrodes of piezoelectric materials on the squirrel-cage bars are optimized to maximize the modal electromechanical coupling factor. An in-house code to simulate the dynamic performance of the rotor with the elastic support-piezoelectric damper system is developed in ANSYS/MATLAB environment. To reduce the computational cost, the following acceleration techniques are adopted: 1) the specific modal synthesis method dedicated to piezoelectric structures is implemented to reduce the order of the original finite element model; 2) based on the principle of equal energy consumption, the equivalent linearization method is carried out to transfer the SSD with nonlinear nature to a frequency-dependent shunted linear impedance, thus the time-consuming nonlinear solver e.g. the harmonic balance method is avoided. The harmonic response of the rotor subjected to unbalanced loads is analyzed numerically. The damping effects of these two piezoelectric damping technologies on the rotor are compared and discussed. Results show that both the resonant shunt and the SSD shunt can reduce the vibration level of the rotor significantly; interconnecting piezoelectric patches with a 180-degree difference in the circumferential direction of the squirrel-cage can reduce the number of piezoelectric shunted circuits to half of the number of squirrel-cage bars.

Presenting Author: Ya Guang Wu School of Energy and Power Engineering, Beihang University

Presenting Author Biography: Post-doc in School of Energy and Power Engineering, Beihang University

Authors:

Yu Hu School of Energy and Power Engineering, Beihang University
Lin Li School of Energy and Power Engineering, Beihang University
Ya Guang Wu School of Energy and Power Engineering, Beihang University
Yu Fan School of Energy and Power Engineering, Beihang University