A multiphysics framework for energy conversion from nonlinear electrostrictive dielectric elastomer generators

In this paper, we present a multiphysics framework for studying energy conversion from highly nonlinear electrostrictive dielectric elastomer generators. This framework investigates the impact of electrostriction on dielectric elastomers’ energy harvesting. Regarding the constitutive equations, we employ constitutive models which relate the dielectric permittivity of an elastomer to a general three-dimensional state of deformation based on the statistical mechanics of a Gaussian polymer chain. An in-house computer code is written based on the developed numerical framework. Two axisymmetric dielectric elastomer generators are studied: a circular diaphragm generator and a cylindrical tube generator. In this research, the case studies are diverse, though they focus on the electrostriction phenomenon. Our study demonstrates that the more negative (positive) the electrostrictive coefficient, the better (worse) the energy harvesting. More specifically, there exist cases in which we have improved the energy harvesting of the circular diaphragm generator and the cylindrical tube generator on average by 41.27, and 40.91 percent, respectively.