Computational Modeling of Electro-Elasto-Capillary Phenomena in Dielectric Elastomers

TL;DR

This paper introduces a finite element model that incorporates surface tension to analyze its impact on the deformation and stability of dielectric elastomers under electromechanical loading, revealing significant effects on instabilities.

Contribution

A novel finite deformation, dynamic finite element model that includes surface tension effects on dielectric elastomers' electromechanical behavior and instabilities.

Findings

Surface tension influences deformation and stability.

Surface tension creates a barrier to instability nucleation.

Transition in instability mechanism depends on elastocapillary length.

Abstract

We present a new finite deformation, dynamic finite element model that incorporates surface tension to capture elastocapillary effects on the electromechanical deformation of dielectric elastomers. We demonstrate the significant effect that surface tension can have on the deformation of dielectric elastomers through three numerical examples: (1) surface tension effects on the deformation of single finite elements with homogeneous and inhomogeneous boundary conditions; (2) surface tension effects on instabilities in constrained dielectric elastomer films, and (3) surface tension effects on bursting drops in solid dielectrics. Generally, we find that surface tension creates a barrier to instability nucleation. Specifically, we find in agreement with recent experimental studies of constrained dielectric elastomer films a transition in the surface instability mechanism depending on the elastocapillary length. The present results indicate that the proposed methodology may be beneficial in studying the electromechanical deformation and instabilities for dielectric elastomers in the presence of surface tension.