Turbulence Models

Turbulence Models

OpenFOAM offers a large range of methods and models to simulate turbulence. The methods include:

  • Reynolds-average simulation (RAS), also known as Reynolds-averaged Navier-Stokes (RANS): The governing equations are solved in ensemble-averaged form, including appropriate models for the effect of turbulence. See the list of incompressible and compressible RAS models for more information.
  • Large eddy simulation (LES): Large turbulent structures in the flow are resolved by the governing equations, while the effect of the sub-grid scales (SGS) are modelled. The scale separation is obtained by applying a filter to the governing equations which also influences the form of the SGS models. The list of LES models contains information about models, LES filters and filter width functions.
  • Detached eddy simulation (DES): Hybrid method that treats near-wall regions with a RAS approach and the bulk flow with an LES approach. DES models are found in the list of LES models.
  • Direct numerical simulation (DNS): Resolves all scales of turbulence by solving the Navier-Stokes equations numerically without any turbulence modelling. DNS simulations can be performed in OpenFOAM using the dnsFoam solver.