Manipulating P-and S-elastic waves in dielectric elastomers via external electric stimuli

TL;DR

This paper explores how external electric stimuli can manipulate P- and S-elastic waves in dielectric elastomers, revealing electric field-dependent wave separation and velocity changes with implications for material design.

Contribution

It provides explicit expressions for wave velocities and demonstrates electric field-induced P-S wave disentangling in dielectric elastomers, considering different material models.

Findings

Electric field can separate P- and S-waves in dielectric elastomers.

P-wave velocity increases with electric field in ideal models.

Divergence angle between P- and S-waves depends on electric stimuli and material properties.

Abstract

We investigate elastic wave propagation in finitely deformed dielectric elastomers in the presence of an electrostatic field. To analyze the propagation of both longitudinal (P-) and transverse (S-) waves, we utilize compressible material models. We derive explicit expressions of the generalized acoustic tensor and phase velocities of elastic waves for the ideal and enriched dielectric elastomer models. We analyze the slowness curves of the elastic wave propagation, and find the P-S-mode disentangling phenomenon. In particular, P- and S- waves are separated by the application of an electric field. The divergence angle between P- and S-waves strongly depends on the applied electrostatic excitation. The influence of the electric field is sensitive to material models. Thus, for ideal dielectric model the in-plane shear velocity increases with an increase in electric field, while for the enriched model the velocity may decreases depending on material constants. Similarly, the divergence angle gradually increases with an increase in electric field, while for the enriched model, the angle may be bounded. Material compressibility affects the P-wave velocity, and, for relatively compressible materials, the slowness curves evolve from circular to elliptical shapes manifesting in an increase of the reflection angle of P-waves. As a results, the divergence angle decreases with an increase in material compressibility.