Vibration Attenuation Study of Curved Panel Treated with Partially Constrained Composite Unaged and Aged NBR (Acrylonitrile-Butadiene Rubber) Elastomers

Background Reduction in structure vibration by dampers during a defined time has attracted widespread attention in the aerospace and automobile industries. Therefore, the comparative study of curved panel structure vibration reduction is very important. Purpose This paper aims to study the damping effect of a curved panel in the presence of unconstrained and constrained composite NBR elastomeric layers, both unaged and aged (high temperature, low temperature, and QUV). Methodology The modal strain energy approach is used to determine placement strategies for elastomeric layer patches. The comparative study shows that the constrained layer damping patches are a more effective way to attenuate vibration for the curved panel when placed at maximum modal strain energy locations. Furthermore, vibration tests of curved panel are conducted by preparing a number of separate samples of unconstrained and constrained composite NBR elastomers patches for each configuration to increase the damping of different modes. Results and Conclusion The results show the effectiveness of modal strain energy technique for placement of constrained composite NBR elastomers patches on the curved panel to achieve desired damping characteristics over a broad frequency range. Subsequently, it also demonstrates that, damping of the curved panel is more influenced due to QUV aged elastomeric patches than high and low temperature aged elastomers patches. Moreover, the reduction in damping of the curved panel is more resisted due to the presence of nano carboxylic graphene (CG)/SiO2 in the aged composite NBR elastomer. The present method elaborates the utility of the technique for placement of constrained elastomeric patches to attenuate structure vibration by modal strain energy and damping reduction resistance against ageing by composite NBR elastomer. [GRAPHICS] .