Consistency and recovery in electroelasticity. Part II: Equilibrium and mixed finite elements Original Research Article

The first part of this paper establishes the concept of consistency for standard finite elements in electroelasticity. This has permitted to trace the origin of certain spurious oscillations affecting the finite element response in terms of stress and electric flux density. In this second part, the consistency analysis is generalized to models which directly involve stress and electric flux density as independent variables. The analysis shows that also these models can suffer from spurious outcomes. However, selecting the approximation functions on consistency basis allows to eliminate, or at least reduce, the undesired oscillations.