Abstract (EN):
Under an active control framework, piezoelectric transducers mounted on a host
structure are directly actuated under a pre-determined control law in order to mitigate mechanical
vibration and/or structural acoustics radiation. Alternatively, they may be connected to passive
electrical circuitry, with electrical impedance defined by the resistive, capacitive and inductive
elements, which is known as resonant shunt damping. Shunt damping somewhat involves
thermal dissipation of the part of the mechanical energy which is converted to an electrical form
and depends upon the electrical impedance generated by the external shunt circuit. Spatially
shaped distributed piezoelectric transducers/electrodes have been successfully used with the objective
of filtering out undesirable mode’s contributions, making them unobservable and uncontrollable
over the bandwidth of interest, through the use of both modal transducers and spatial
filtering technologies. As evidenced from the analysis of spatially shaped transducers, they may
yield higher generalized modal electromechanical coupling coefficients that when conveniently
used may increase the shunt damping performance. This possibility is investigated in this article
for a two-layered adaptive beam structure with spatially shaped resonant shunted piezoelectric
transducers. A phenomenological electromechanical analytical model of beams with modal
sensing/actuation via spatially shaped distributed shunted piezoelectric transducers/electrodes is
derived and the underlying performance is assessed and the advantages discussed.
Idioma:
Português
Tipo (Avaliação Docente):
Científica
Contacto:
jdr@fe.up.pt