Finite element modeling of temporal evolution of the quasi-piezoelectric d33 coefficient of cellular piezoelectret Polypropylene film

► The microvoids in piezoelectret are modeled by the hollow oblate tetrakaidecahedra. ► Temporal evolution of d33 of cellular piezoelectret is given by finite element model. ► Temporal evolution of d33 is analyzed with respect to various parameters. ► Experiments on time spectra of d33 are compared with the finite element results.