One of the solver’s primary objectives is not only to solve the Navier Stokes equations but to solve fully coupled FSI problem where the structural part could be any Lagrangian model of LS-DYNA. The setting up of the mechanical problem is therefore done the same way as for a classic LS-DYNA analysis. All FSI boundaries are Lagrangian and deform with the structure allowing exact imposition of boundary conditions. Both the structural explicit and implicit solvers can be activated resulting in weak or strong FSI analysis. Three coupling directions are available for FSI analysis :