Shunted piezoelectric patches on auxetic microstructures for the enhancement of band gaps

Certain frequency ranges where waves do not propagate, and thus, vibrations are suppressed, are called band gaps. In the present paper, the appearance and the behavior of such areas are investigated on star-shaped auxetic microstructures, which are equipped with shunted piezoelectric elements. The optimal position of the piezoelectric patches is found using genetic algorithms, considering the maximization of the electromechanical coupling coefficient. A genetic algorithm is also used for the calculation of the values of the electrical parameters of the resonant shunt circuit, with objective the maximization of certain band gaps. The results indicate that the proposed technique can be used for the maximization of band gaps at certain frequency ranges, as well as at frequency bands which have not been considered in the optimization problem of the mechanical microstructure.