Set up an axisymmetric case

A pipe, a nozzle, a jet — anything with rotational symmetry — is solved as a wedge of a few degrees about the axis, one cell thick, with wedge patches on the two cut faces.

Runs on the free tier.

Build the wedge

1. Select Operations.
2. Under Add operation, choose Extrude a patch.
3. Set Mode to Wedge (axisymmetric).
4. Choose the Source patch — the surface swept into the volume.
5. Set Angle. The hint gives five degrees as the usual wedge: small enough that one cell across it is a reasonable model.
6. Set Axis X, Axis Y and Axis Z to the axis of revolution.
7. Press Generate mesh.

Operations run in order after the mesh is generated and before it is checked, so the quality figures you see are the mesh you will actually solve on.

Declare the two faces

1. Select Boundary conditions.
2. If the patch names do not match the mesh, take the mesh’s names with Use the mesh’s patches; otherwise add them with + Add patch.
3. Set both cut faces to Type Wedge (axisymmetric).

It takes no parameters — it is a purely geometric condition applied to every field.

Exactly two. One is an open domain and three does not describe a wedge; the Problems tab counts them and says how many it found.

Do not also set two-dimensional

empty and wedge are alternative ways of removing the same direction. A case declared as both is rejected. Leave Two-dimensional off under Mesh.

Check it worked

• The Problems tab is clear of the wedge-count and 2-D/axisymmetric errors.
• Quality passes — a wedge that is too wide, or a mesh that is not one cell across it, shows up here first.
• A slice through the solution under Post-processing shows the field varying along and across the wedge, not around it.