Local Immersed Boundary Method on body-conformal grids for the capture of geometrical features in aerodynamic simulations
Rayan Nkenfack Soppi, F. Basile, Stéphanie Péron, Maher Lagha, Imadeddine Hammani · 2024
This paper presents a Local Immersed Boundary Method (LIBM) applied on curvilinear grids to simulate turbulent flows around obstacles with geometrical complex details.With this approach, the governing equations are solved with a finite volume solver using a wall-resolved technique over the body-conformal region of the mesh, whereas an Immersed Boundary Method (IBM) is applied to account for the complex geometrical details.The IBM method consists in forcing the solution through a wall function at some discretizations points close to the immersed details.When the background mesh is too coarse in the vicinity of the immersed obstacles, mesh adaptation is performed to properly capture the flow physics induced by the presence of the immersed obstacle.The preprocessing is achieved with Cassiopée modules and the flow simulation is performed by solving the compressible Reynolds-Averaged Navier-Stokes (RANS) equations with the flow solver CODA (CFD for ONERA-DLR-AIRBUS) 1 .This approach has been applied to simulate turbulent flows around a 2D multi-element airfoil.The results obtained show that the local IBM approach is an efficient method to deal with geometrical complex obstacles as it allows a significant reduction of the mesh generation effort without compromising the flow solution accuracy.