THE REDUCTION OF VIBRATIONAL-ENERGY FLOW IN A PERIODICALLY SUPPORTED BEAM

The reduction of vibrational energy flow in a spatially periodically supported beam is studied. The influence of the excitation location on the transmitted and travelling energy flows is investigated. For different propagation bands, the vibrational energy transmitted into the beam can be reduced to a minimum by suitably adjusting the excitation location. No matter where the beam is excited, the energy flows along the beam in the positive and negative directions are the same in magnitude and equal to one half of the transmitted power. The effect of structural damping on the energy flow is also studied. In this case the periodic beam is excited at the mid-point of one bay. The transmitted power is effectively controlled by damping near the bounding frequencies of the odd propagation bands. The energy flow is effectively decreased by damping in the propagation bands. © 1991.