Open AccessCharacterization of Contact Kinematics and Application to the Design of Wedge Dampers in Turbomachinery Blading: Part I — Stick-Slip Contact Kinematics
Author(s) -
BeenDer Yang,
Chia-Hsiang Menq
Publication year - 1997
Publication title -
volume 4: manufacturing materials and metallurgy; ceramics; structures and dynamics; controls, diagnostics and instrumentation; education; igti scholar award
Language(s) - English
Resource type - Conference proceedings
DOI - 10.1115/97-gt-019
Subject(s) - damper , kinematics , vibration , structural engineering , turbomachinery , stiffness , slip (aerodynamics) , wedge (geometry) , engineering , mechanical engineering , physics , acoustics , classical mechanics , aerospace engineering , optics
Friction dampers are often used in turbine design to attenuate blade vibration to acceptable levels so as to prolong blades’ service life. A wedge damper, also called a self-centering blade-to-blade damper, can provide more design flexibility to meet various needs in different operating conditions when compared with conventional platform dampers. However, direct coupling of the two inclined friction interfaces of the wedge damper often leads to very complex contact kinematics. In Part I of this two-part paper, a dual-interface friction force model is proposed to investigate the coupling contact kinematics. The key issue of the model formulation is to derive analytical criteria for the stick-slip transitions that can be used to precisely simulate the complex stick-slip motion and, thus, the induced friction force as well. When considering cyclic loading, the induced periodic friction forces can be obtained to determine the effective stiffness and damping of the interfaces over a cycle of motion. In Part II of this paper, the estimated stiffness and damping are then incorporated with the harmonic balance method to predict the forced response of a blade constrained by wedge dampers.