Spalart-Allmaras Improved Delayed Detached Eddy Simulation (IDDES)

Properties

• One equation model based on a modified turbulence viscosity, $\tilde{\nu}$

Model equations

The model equations are the same as used by the DES variant of the model, with a different approximation for $\tilde{d}$:

$$\tilde{d} = \max \left( \tilde{f_d} (1 + f_e) L_{RAS} + (1 - \tilde{f_d}) L_{LES}, SMALL \right)$$

Default model coefficients

Initialisation

Usage

The model is specified using:

LES
{
    turbulence      on;
    LESModel        SpalartAllmarasIDDES;
}

Boundary conditions

Inlet

• fixedValue

Outlet

• Constrained outlet

Walls

• wall functions

Further information

Source code:

• Foam::LESModels::SpalartAllmarasIDDES

References:

• Gritskevich et al. 22