Passive damping augmentation of a vibrating beam using pseudoelastic shape memory alloy wires

This paper examines the effectiveness of pseudoelastic shape memory alloy (SMA) wires for passive damping of flexural vibrations of a clamped-free beam with a tip mass. A finite-element model of the system is developed and validated with experimental results. The SMA behavior is modelled using amplitude-dependent complex modulus. Numerical simulations indicate that the damping introduced by the SMA wires will increase for higher excitation-force amplitudes that produce higher strain levels in the SMA wires. Increasing the wire cross-section area provides more damping at low force-excitation amplitudes,. but reduced damping at higher amplitudes. The angle between the beam and the SMA wires is an influential parameter, and a value in the 10-20degrees range was found to introduce maximum damping. The underlying physical mechanisms are examined in detail. System damping depends only mildly on the SMA wire length, and is unaffected by the tip mass. (C) 2002 Academic Press.