Stratos: a code for 3D free surface flows with floating constraints

This report presents a brief discussion of the theoretical aspects and practical implementation of STRATOS . STRATOS is a 3D code for the simulation of hydrodynamic flows for incompressible fluids, in the presence of a free surface, capable of simulating the interaction between the free surface and a floating object via Lagrange multipliers. In section 1, we review the governing equations for free surface flows, the associated boundary and initial conditions, and we introduce the floating constraint. The numerical approximation is described in section 2, where we explore the temporal discretization, the physical domain discretization, and the finite element approximation that are implemented in STRATOS . In section 3 we analyze in detail the structure and the main subroutines of STRATOS . The explanation of how to modify STRATOS subroutines depending on the problem to solve is postponed to section 4, where some numerical tests of increasing complexity are explained in detail. ∗Corresponding Author. Email: Antonio DeSimone ; Tel.: +39 040 3787445; Fax: +39 040 3787528