The implementation of an implicit LU-SGS scheme steady solver based on OpenFOAM

OpenFOAM is a popular open source numerical simulation CFD software. The density-based solvers released by the official are all explicit schemes. LU-SGS is an implicit scheme, LTS is a time marching method that can accelerate the convergence of a steady state problem. In this paper, a density-based implicit solver using LU-SGS scheme and LTS for steady state compressible problems based on OpenFOAM is implemented. The detail of the implementation of the solver is introduced. Oblique shock in OpenFOAM and transonic inviscid compressible flow pass through the NACA0012 airfoil are tested. The comparison of the results has shown a better convergence performance using the LU-SGS-LTS solver.