The aim of this paper is to understand the performances of different finite elements
in the space discretization of the Finite Element Immersed Boundary Method. In
this exploration we will analyze two popular solution spaces: Hood-Taylor and Bercovier-
Pironneau (P1-iso-P2). Immersed boundary solution is characterized by pressure discontinuities
at fluid structure interface. Due to such a discontinuity a natural enrichment
choice is to add piecewise constant functions to the pressure space. Results show that
P1 + P0 pressure spaces are a significant cure for the well known “boundary leakage”
affecting IBM. Convergence analysis is performed, showing how the discontinuity in the
pressure is affecting the convergence rate for our finite element approximation
