An efficient IMEX-DG solver for the compressible Navier-Stokes equations for non-ideal gases.

• Novel IMEX-DG solver for the compressible Navier-Stokes equations for non-ideal gases. • Suitable fixed point procedure for the general cubic equation of state. • Adaptive simulations with appropriate refinement indicators for real gases. • Low Mach efficient solver keeping full second order accuracy also for higher Mach regimes. • Analysis of second order ARK-IMEX method in terms of absolute monotonicity. We propose an efficient, accurate and robust IMEX solver for the compressible Navier-Stokes equations describing non-ideal gases with general cubic equation of state and Stiffened-Gas EOS. The method is based on an h -adaptive Discontinuous Galerkin spatial discretization and on an Additive Runge Kutta IMEX method for time discretization. It is specifically tailored for low Mach number applications and allows to simulate low Mach regimes at a significantly reduced computational cost, while maintaining full second order accuracy also for higher Mach number regimes. The method has been implemented in the framework of the deal.II numerical library, whose adaptive mesh refinement capabilities are employed to enhance efficiency. Refinement indicators appropriate for real gas phenomena have been introduced. A number of numerical experiments on classical benchmarks for compressible flows and their extension to real gases demonstrate the properties of the proposed method. [ABSTRACT FROM AUTHOR]