12.2 Choosing a Turbulence Model

It is an unfortunate fact that no single turbulence model is universally accepted as being superior for all classes of problems. The choice of turbulence model will depend on considerations such as the physics encompassed in the flow, the established practice for a specific class of problem, the level of accuracy required, the available computational resources, and the amount of time available for the simulation. To make the most appropriate choice of model for your application, you need to understand the capabilities and limitations of the various options.

The purpose of this section is to give an overview of issues related to the turbulence models provided in ANSYS FLUENT. The computational effort and cost in terms of CPU time and memory of the individual models is discussed. While it is impossible to state categorically which model is best for a specific application, general guidelines are presented to help you choose the appropriate turbulence model for the flow you want to model.

For more information about the Reynolds-Averaged approach of the DES model versus the LES model, see this section in the separate Theory Guide.

For more information about Reynolds (ensemble) averaging, see this section in the separate Theory Guide.

For more information about the Boussinesq approach versus Reynolds Stress Transport models, see this section in the separate Theory Guide.