Conservative Coupling Strategy with Non-Coincident Meshes in Partitioned Fluid Structure Interaction Problems

Abstract

Numerical simulations of fluid structure interaction problems have become affordable for a wide range of engineering applications. However, since the complexity of such simulations has increased due to the introduction of other physical phenomena like thermodynamics and acoustics, it is convenient to use a partitioned strategy whenever possible. The coupling of well developed and reliable computer codes can tackle, without introducing major modifications, the numerical solution of such problems. In this scenario, it is also desirable to count with the flexibility of using different discretizations for computing the solution of each physical problem. However, this introduces the requirements of projecting the solution from the interface of one subdomain to that of its neighbour subdomain, to track the displacement of the boundaries and to sychronize the solvers to be able to use differente time step sizes for the computations. In this work, a conservative projection and a tracking algorithm are analyzed by computing the solution of benchmark problems of the fluid structure interaction kind with non-coincident meshes at the interfaces. The accuracy, consistency and conservativeness of the implemented algorithms are evaluated and compared to those of another ones mentioned in the literature. The strengths and weaknesses of both algorithms are finally mentioned.