I have made a rectangular domain and want to add some small rectangular surface to represent the inlet and outlet opening. Making the surface from skeches is possible but it causes error when meshing. Is there any convenient method for making such kind of opening by suface in the WorkBench Design Modeler?

Hi Coriolius,

Select the surface and click on the sketching tab, this will automatically create a plane on your surface. Sketch the area you want and choose Extrude. Under the extrude options, choose imprint face.

This will imprint your sketch onto the faces. How many faces will depend on what depth options you choose. To limit it to the face you are sketching on, choose "To Next" or "To Face" and select the face.

Regards, Robin