Abstract:Based on the thermodynamic theory of equilibrium state and combined with the Gent superelastic material model, this study established a force-electric coupling constitutive model describing the circular dielectric elastomer thin film actuator under the combined action of internal pressure and voltage. Through theoretical analysis and numerical calculation, the influence of inclusion size on the force-electric response behavior of circular films was systematically studied. The numerical simulation results show that the size variation of inclusions mainly affects the inner boundary of the film rather than the outer boundary. More importantly, increasing the size of inclusions can effectively suppress the violent fluctuations of the vertical displacement, tensile ratio and true stress of the film under the action of voltage, and significantly improve the electric field distribution characteristics of the film: on the one hand, it makes the electric field distribution at the inner boundary of the film tend to be stable; on the other hand, it enhances the uniformity of the overall electric field, resulting in a significant increase in the critical electric field strength of the film. This research provides important theoretical basis and technical guidance for the optimal design of high-performance dielectric elastomer film actuators.