Nonconforming finite element formulation for the simulation of impedance cardiography

We present a nonconforming Finite Element (FE) formulation for the electro-quasistatic case. The formulation allows a grid generation for each sub-domain individually. At the nonconforming interfaces, we apply a Nitsche-type mortaring, which can also be interpreted as a DG-IP (Discontinuous Galerkin-Internal Penalty) formulation. Thereby, the continuity of the electric potential and the electric flux in the discrete setting is guaranteed. The system matrix remains symmetric, and the necessary penalty factor can be chosen in a wide range without deteriorating the numerical solution. The application to impedance cardiography demonstrates the practical applicability, especially its advantage toward simplification of the grid generation.