Multicomponent real gas 3-D-NSCBC for direct numerical simulation of reactive compressible viscous flows

The topic of this paper is to propose an extension of the classical one-dimensional Navier–Stokes boundary conditions (1-D-NSCBC) for real gases initially developed by Okong’o and Bellan [1] to a 3-D-NSCBC formulation based on the work of Lodato et al. [2] and Coussement et al. [3]. All the differences due to the real gas formulation compared to the perfect gas formulation proposed in [3] are emphasized. A new way of determining the pressure relaxation coefficient is introduced for handling transcritical flows crossing the boundary. The real gas 3-D-NSCBC are then challenged on several test cases: a two-dimensional subsonic vortex convection, a subsonic supercritical bubble convection and a flame vortex interaction. All these test cases are performed by direct numerical simulation of multicomponent flows. It shows the stability of the boundary conditions without creating any numerical artifact.