12.11.1 Setting Up the Spalart-Allmaras DES Model

ANSYS FLUENT uses this equation (in the separate Theory Guide) to compute the value of the length scale $\tilde{d}$ for the Spalart-Allmaras model. By default, the empirical constant $C_{\rm des}$ is set to 0.65. You can change its value in the Cdes field under Model Constants. The following options are available for this model:

• vorticity-based production (Section  12.13.3)

• strain/vorticity-based production (Section  12.13.3)

• low-Re damping (Section  12.13.8)

• delayed DES (Section  12.13.4)

• viscous heating (always activated for the density-based solvers) (Section  12.13.1)

Figure 12.11.1: The Viscous Model Dialog Box Displaying the Spalart-Allmaras Detached Eddy Simulation Model Options