Turbulent Viscosity
Turbulent viscosity is a condition for a
Domain in the Flow Analysis Tree.
You can specify the type of eddy viscosity model for a selected
Domain for the
Turbulence module in the Properties panel. There are two models in the eddy viscosity model:
• Standard K-Epsilon Model
• Renormalization Group (RNG) Model
You can select the
RNG model and the associated
constants for a selected
Volume under the
Turbulence module in the Properties panel. The
RNG model may be more accurate than the
standard k-epsilon model for flows with stagnation and separation. The following two additional constants are hard-coded for the
RNG model: η
0=4.38 and β=1.92.
Turb. Viscosity Relaxation
Turb. Viscosity Relaxation in the
Turbulence module controls the amount of correction applied during each iteration, using the following formula for the
turbulent viscosity. You can set
Turb. Viscosity Relaxation for a selected
Domain under the
Turbulence module in the Properties panel.
The default 0 value of Turb. Viscosity Relaxation is the most liberal and allows full application of the correction. Turb. Viscosity Relaxation ranges from 0 to 1. A value of 0 is recommended if no problem occurs with the convergence. Higher values (>0) are recommended if needed to prevent a solution from diverging. A Turb. Viscosity Relaxation value of 1 is the most restrictive and allows no correction of the solution from one iteration to the next.
