Updated Lagrangian/Arbitrary Lagrangian-Eulerian framework for interaction between a compressible neo-Hookean structure and an incompressible fluid

We propose a numerical method for a fluid-structure interaction problem. The material of the structure is homogeneous, isotropic, and it can be described by the compressible neo-Hookean constitutive equation, while the fluid is governed by the Navier-Stokes equations. Our study does not use turbulence model. Updated Lagrangian method is used for the structure and fluid equations are written in Arbitrary Lagrangian-Eulerian coordinates. One global moving mesh is employed for the fluid-structure domain, where the fluid-structure interface is an 'interior boundary' of the global mesh. At each time step, we solve a monolithic system of unknown velocity and pressure defined on the global mesh. The continuity of velocity at the interface is automatically satisfied, while the continuity of stress does not appear explicitly in the monolithic fluid-structure system. This method is very fast because at each time step, we solve only one linear system. This linear system was obtained by the linearization of the structure around the previous position in the updated Lagrangian formulation and by the employment of a linear convection term for the fluid. Numerical results are presented. Copyright (C) 2016 John Wiley & Sons, Ltd.