[AKll]

Hello everyone,

I know, this topic is basic and should be answered already, however, unfortunately I didn't find the answer in old threads or through youtube videos.
I am using Icem and Ansys on my universities cluster, although, the program usage is provided, I don't have access to the help function of the programs or any files in the installation folders.
Google got me a CFD User's guide and programmer's guide, both didn't hold the answer I was looking for.

My question:
I have a cascade section of a turbine, which I am about to mesh with rotational periodicity.
Because of the geometries complexity I am not able to use blocking, so I am using unstrucutred meshing.

Now my work chain is the following:

under Mesh, Global Mesh Parameters, I am defining the Global Mesh Size, Shell Meshing Parameters, Volume Meshing Parameters and the Set up Periodicity.

Here, I set the rotational axis (x) and the base, which is the point on that axis where the geometry begins and the angle of the cascade section.

Each Menu I send off with a click on apply, which gives me a message in the message window "periodicity has been defined" etc.

Now, I proceed with choosing the compute option under the Meshing menu.
I am choosing Octree Mesh (I read online, Delauny isn't capable of periodicity).
So I skip the surface meshing part and go straight to volume meshing.
I click compute and the mesh is constructed.

Now, when I check that mesh, under the edit mesh menu, and I choose to check for periodicity problems, it writes out:
"There is no periodicity defined in the mesh"

What am I missing or skipping?

[Gert-Jan]

It is nice to have a periodic mesh. But it is not strictly necessary.
In e.g. CFX, it is possible to make periodic boundaries while the mesh is not periodic. Then simply define a periodic GGI, and CFX will do the thing.

Certainly, it is better to have clean periodic meshes. But now it is difficult to help without any pictures showing what you did and where it fails. Can you add some (using the menu "Go Advanced")

[AKll]

Thank you very much for that reply!

It actually works quite fine with just the preriodicity defined within CFX.

Unfortunately, I am not allowed to share any pictures or data of the model, however, I build a similar case of a simplified geometry and when walking through the same steps, the check mesh report gives me the message that there has been a fix in closest periodicity points, which makes me believe that the periodicity has been defined in the mesh.

Now, I think it's due to the geometry that there is a problem for ICEM to automatically define the periodicity in my more complex main mesh.

I'll re-check with re-building the surfaces that are supposed to be periodic.

Again, thanks for the hint to let Ansys CFX handle it, that will be my go to "solution" for now.