Resonance Suppression in Multi-DOF Rotating Flexible Structures Using Order-Tuned Absorbers

Abstract

This paper considers the dynamic response and order-tuning of vibration absorbers fitted to a rotating flexible structure under traveling wave (TW) engine order excitation. Of specific interest is the extension of previous results on the so-called no-resonance zone, that is, a region in linear tuning parameter space in which the coupled structure/absorber system does not experience resonance over all rotation speeds. The no-resonance feature was shown to exist for cyclic rotating structures with one structural and one absorber degree-of-freedom (DOF) per sector. This work uses a higher-fidelity structural model to investigate the effects of higher modes on the cyclically-coupled system. It is shown that the no-resonance zone is replaced by a resonance-suppression zone in which one structural mode is suppressed, but higher-order resonances still exist with the addition of the absorbers. The results are general, in the sense that one vibration mode can be eliminated using a set of identically-tuned absorbers on a rotating structure with arbitrarily many DOFs per sector.

Vibration absorbers for a rotating flexible structure with cyclic symmetry: nonlinear path design

“…Similar results using higher-fidelity blade models is reported in [34]. The linearized sector models and the linear absorber tuning order are discussed in Sect.…”

“…Local stability of a stationary point v = (ū,¯ ,v,ς) T , the elements of which are defined implicitly by (34), can be obtained by considering the small perturbations…”

Optimum Design of Damped Vibration Absorber for Rotationally Periodic Structures

“…The flexural stiffness of each blades are modeled with a linear torsional springs in points a and b and inter-blade coupling and aerodynamic damping is modeled in the distances of r a and r b and with linear springs and dampers [18]. The blade's dynamics are shown with the coordinates of θ and θ .…”

“…These absorbers exploit the centrifugal field arising from rotation so that they are tuned to a given order of rotation, rather than to a fixed frequency. By tuning each undamped absorber within a small but finite range, known as no resonance zone, resonance can be avoid for systems with cyclic symmetry [17,18]. In this investigation, the importance of damping is considered and effect of damping of centrifugally driven ordertuned vibration absorber on blade vibration is studied.…”

بررسی تحلیلی قفل‌شدگی تشدید در سیستم‌های نامیزان دوار و اثر یک نامیزانی دوار آزاد بر رفتار سیستم

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