Structural damping enhancement using a novel approach - a forward look

This paper considers two aspects for enhancing structural damping using pas sive, but novel, methods. Attempting to take a forward look to the twenty-f irst century, the concept of using biological and evolutionary methods to ' grow' damping material on the surface of a vibrating component is described . A simple cantilever beam is used as the component and a 'free-layer' visc oelastic damping treatment is 'grown' on the structure in such a way as to provide optimum damping over a frequency bandwidth that encompasses flexura l and torsional modes of vibration. To enhance the 'controllability' of the damping, the viscoelastic material is considered as a cellular material di splaying a negative Poisson's ratio and it is shown that for the 'free-laye r' treatment it is possible to produce a range of modal loss factors by cha nging the cell geometry. Only numerical studies are used and no experimenta l validation has been carried out, the idea being to stimulate ideas for fu ture structural damping concepts.