International audienceThis paper presents advancements toward a monolithic solution procedure and anisotropic mesh adaptation for the numerical solution of fluid-structure interaction with complex geometry. First, a new stabilized three-field stress, velocity, and pressure finite element formulation is presented for modeling the interaction between the fluid (laminar or turbulent) and the rigid body. The presence of the structure will be taken into account by means of an extra stress in the Navier-Stokes equations. The system is solved using a finite element variational multiscale method. We combine this method with anisotropic mesh adaptation to ensure an accurate capturing of the discontinuities at the fluid-solid interface. We assess the behavior and accuracy of the proposed formulation in the simulation of 2D and 3D time-dependent numerical examples such as the flow past a circular cylinder and turbulent flows behind an immersed helicopter in a forward flight

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International audienceAn efficient method to compute the permeability of disordered fibrous arrays is proposed. A stabilized mixed finite element method is used with an immersed domain approach to represent the porous material at its microscopic scale. Therefore, the Stokes equations are solved in the whole domain (including solid part) using a penalization method. The accuracy is controlled by refining the mesh around the fluid-solid interface defined by a level-set function. Using homogenization techniques, the permeability of an RVE is obtained. Furthermore, a new method to generate disordered fibers in function of the porosity, Φ, and other microstructural parameters is proposed and a study of the effect of inter-fiber spacing on K, the permeability tensor, is performed. This task was achieved using parallel computation and over 460 simulations were carried out in two-dimensional RVEs consisting of over 555 fiber