Model Wizard
Note: These instructions are for the user interface on Windows but apply, with minor differences, also to Linux and macOS.
1
If COMSOL is already open, you can start the Model Wizard by choosing  New from the File menu and then click  Model Wizard.
The Model Wizard guides you through the first steps of setting up a model. The next window lets you choose the dimension of the modeling space.
2
In the Select Physics tree, expand the nodes Fluid Flow > Nonisothermal Flow > Turbulent Flow and then double-click  Turbulent Flow, k-ε to add it to the Added physics interfaces list. You can also right-click Turbulent Flow, k-ε and choose  Add Physics.
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