Vibroacoustic FE analysis of an adaptive plate with PZT actuator/sensor pairs connected to a multiple-mode, electric shunt system

摘要

The present work aims to simulate, using the finite element method (FEM), the piezo-shunting of a PZT actuated vibrating plate, i.e. the connection to a collocated PZT sensor of a multiple-mode electric shunt system to damp the plate vibration. The simulation is further extended to some vibroacoustical aspects, to show the piezoelectric-vibrational-acoustic frequency response, and also the free sound radiation of the plate into air. The FEM analytical basis of the piezo-shunted vibrating plate and its sound radiation are reviewed together with the description and FE formulation of the electric shunt system. The piezo-shunting effect in the damping of the plate vibration is smaller than in the case of a beam, because not all the eigenmodes can be actuated or damped. This effect, which is more apparent at higher frequencies, depends strongly on the position of the plate, but not on the thickness, of the PZT sensor. The acoustic radiation peaks results are good in the same eigenfrequencies as the mechanical vibration peaks of the plate, but with a much larger damping width.