Geometric optimization of dry friction ring dampers

In operation, blisks are subject to dynamic loading, which result in large response amplitudes near resonance. To reduce the response level and prevent damages caused by high cycle fatigue, friction damping sources are introduced to dissipate vibrational energy. The effectiveness of friction dampers depends not only on the mode shape of the vibrational mode being excited, but also on the damper material and geometrical properties. To create a robust design, it is necessary to parametrize the damper geometry, and to study the effect of geometric parameters on energy dissipation. The effectiveness of the damper is determined by evaluating the reduction in forced responses due to friction damping. To compute the nonlinear forced responses of a blisk-damper system, a reduced-order model is constructed with the method of coherent ring dampers (CoRiD). The equations of the reduced-order model are efficiently solved by the harmonic balance method (HBM). A parametric study on the effectiveness of a V-shaped friction ring damper is presented, focusing on the sensitivity of the damper effectiveness to variations of the dimensions of the damper geometry.