Design of dry friction dampers for thin-walled structures by an accelerated dynamic Lagrange method

Abstract

The low inherent damping for thin-walled structures often leads to prominent vibrational problem. This paper proposes a friction patch to enhance the damping for thin-walled structures. The damping patch is simple in structure and easy to adjust the normal preload. Based on a beam finite element model, parameters including geometry, stiffness and position of the proposed damper are optimized numerically. The steady-state response of the system is calculated by the DLFT in the frequency domain efficiently with high accuracy. The damping performance of the friction patch is quantified by the resonant amplitude for the target mode. The design guidelines summarized from numerical simulation are experimentally verified through a cantilever beam. Four optimized friction patches are implemented to a complex industrial thin-walled structure. Results show that the well-designed friction patches provide over 40% vibration reduction with less than 0.83% additional mass of the host structure for different modes.