Modeling Ionic Polymer Metal Composites with COMSOL: Step-by-Step Guide

Considerable effort has been put into modeling the physics of the electromechanical transduction phenomenon of ionic polymer metal composites (IPMCs). A broad way to categorize the existing models is by how the underlying physics is described. The first category is made up of rather empirical current-displacement relation models, often based on the electric circuit equivalent description. The second category of the models explicitly considers the ionic flux inside the material. In this chapter, we consider the latter, namely physics-based IPMC electromechanical and mechanoelectrical transduction models. Although the basic equations of the physics-based models of IPMCs have been established, it can take a significant amount of time and effort to implement them for calculations. Furthermore, freely available basic models of IPMCs would greatly benefit researchers and engineers by being a basis for developing more complicated models according to the research or design needs. To make the fundamental models of IPMCs more applicable in system and application designs, an explicit foundation of how to implement the equations is needed. Therefore, the FEM-based implementation of the model with all necessary boundary conditions is presented—this is called the modeling framework of IPMCs. Step-by-step guidelines of how to implement a basic model of IPMCs in COMSOL Multiphysics® modeling software are provided. COMSOL Multiphysics® is a registered trademark of COMSOL AB. The underlying equations and boundary conditions for the electromechanical and mechanoelectrical transduction model implementations are explicitly described first. Thereafter, sample models with illustrations are introduced followed by a brief analysis of modeling results.