Models define the primary variables of the simulation, including pressure, temperature and velocity, and what mathematical formulation will be used to generate the solution. In this example, the flow is turbulent and incompressible. The Segregated Flow model will be used together with the standard K-Epsilon turbulence model.
The default continuum is automatically named Physics 1 when the mesh is imported. To give the continuum a more appropriate name:
The Rename dialog will appear.
To select appropriate physical models for the air continuum:
Open the Continua node, right-click on the Air node and choose item Select models...
The Physics Model Selection dialog will guide you through the model selection process by showing only options that are appropriate to the choices made so far. Using the same technique as in the previous step:
Now deselect the dialog's Auto-select recommended physics models option. This is because the standard K-Epsilon model will be used in this case instead of the realizable two-layer K-Epsilon model, which is the STAR-CCM+ default.
The Physics Model Selection dialog should look as shown below when you are done.
The color of the Air node has turned from gray to blue to indicate that models have been activated.
Save the simulation by clicking on the 
(Save) button.
