Some attempts to couple distinct fluid models

We present in this paper a review of some recent work dedicated to the numerical interfacial coupling of fluid models. One main motivation of the whole work is to provide some meaningful methods and tools in order to compute unsteady patterns, while using distinct existing CFD codes in the nuclear industry. Thus, the main objective is to derive suitable boundary conditions for both codes to be coupled. A first section is devoted to a review of some attempts to couple: (i) 1D and 3D codes, (ii) distinct homogeneous two-phase flow models, (iii) fluid and porous models. Emphasis is given on comments and references to companion work on similar problems. We detail in the second part some way to couple a two-fluid hyperbolic model and an homogeneous relaxation model. The latter is essentially motivated by practical applications in the nuclear industry.