Viscoelastic damping design - Experimental analysis of optimized constrained layer damping treatments at different ambient temperatures

Constrained Layer Damping (CLD) is an established technology for passive vibration damping. Vibrational energy is dissipated by forcing a viscoelastic material into shear strain. However, the damping performance of CLD treatments is highly dependent on the temperature and the design of such structures can be tailored to operational conditions. This paper presents an experimental analysis of shape-optimized CLD treatments over a temperature range from -20 °C to +20 °C. The samples were designed and manufactured with respect to maximum damping of the first bending mode at minimum and maximum temperature. Eigenfrequencies and damping ratios identified from a modal test in a climatic chamber are compared with those obtained from numerical simulations. The comparison shows a good correlation of the modal parameters. The results demonstrate that using the widths of virtually segmented core and face layers as design parameters is a valid approach for shape optimization of CLD treatments. Furthermore, it is proven that the optimal shape of a CLD treatment is temperature-dependent and that its damping performance varies with the ambient temperature condition.