The immersed boundary method (IBM), proposed by Peskin for studying flow patterns around heart valves  [3], has been applied to a wide range of problems including arterial blood flow  [4], modelling of the cochlea  [5], modelling of red blood cells in Poiseuille flow  [6] and flows involving suspended particles  [7]. A comprehensive list of applications can be found in  [8]. The IBM is both a mathematical formulation and a numerical scheme for fluid–structure interaction problems. As mentioned above, in a classical fluid–structure interaction problem, the fluid and the structure are considered separately and then coupled together via some suitable jump conditions. In the IBM however, the structure–which is usually immersed in a Newtonian fluid–is viewed as being part of the surrounding fluid. This means that only a single equation of motion needs to be solved (i.e. a one-phase formulation). Additionally, the IBM allows the immersed structure to move freely over the underlying fluid mesh, alleviating the need for the remeshing required in a classical formulation.
