[Julian121]

I need to define an interface between two domains as shown in the attached photo. CFX by default assumes it is a wall boundary unless an interface is defined between the domains.
I have 3 doamins:
Rotor
Upstream of Rotor
Casing Treatment
I have defined an interface between upstream domain and rotor but when I define another interface between the casing treatment and the rotor (the same boundary) I got an error that one or more of location specified for this interface is already being used for another interface.
Does anyone know how a boundary can be used to define interface between two separate domains in CFX?

[ghorrocks]

CFX cannot handle the same surface being used in two interfaces. You are going to have to juggle things around so this does not occur.

For example: If surface A interfaces with surface B, and surface C also interfaces with surface B; then set up a single interface with surface A and C on one side and surface B on the other.

[Julian121]

Originally Posted by ghorrocks

CFX cannot handle the same surface being used in two interfaces. You are going to have to juggle things around so this does not occur.

For example: If surface A interfaces with surface B, and surface C also interfaces with surface B; then set up a single interface with surface A and C on one side and surface B on the other.

The pitch angle ratio is not constant between the domains. Can I specify pitch angle for three sides? CFX only takes two angles.
Rotor: 9.47 degrees
Upstream: 9.47 degrees
Casing Treatment: 9 degrees

[ghorrocks]

No you cannot specify a pitch angle for 3 sides. The interface only has 2 sides and my proposal just combined two sides together.

But on closer inspection of your geometry I don't think you need to do this at all. You just need to split the faces and you will have 3 separate interfaces, each with only a single face group on each side, and you can define any pitch ratio you like on any interface.

[Julian121]

Originally Posted by ghorrocks

No you cannot specify a pitch angle for 3 sides. The interface only has 2 sides and my proposal just combined two sides together.

But on closer inspection of your geometry I don't think you need to do this at all. You just need to split the faces and you will have 3 separate interfaces, each with only a single face group on each side, and you can define any pitch ratio you like on any interface.

Thank you for the suggestion.
I have been trying to split the rotor inlet for days!
I have used DesignModeler "face split" but as soon as a change is made to the rotor inlet, Turbogrid cannot be used to generate mesh.
I tried to split face in ICEM but I do not have much experience with ICEM.
Can CFX be used to split the face?

[ghorrocks]

If you want to edit the mesh you will need ICEM. All the other software you mentioned cannot do it. In ICEM you have full control over the mesh, but you need to know how to use it. This can take a little practise.

[Julian121]

Originally Posted by ghorrocks

If you want to edit the mesh you will need ICEM. All the other software you mentioned cannot do it. In ICEM you have full control over the mesh, but you need to know how to use it. This can take a little practise.

Should I use split mesh or segment surface in ICEM to split the rotor inlet into two parts?
Can I use rotor mesh from Turbogrid or structured mesh should be generated in ICEM as well?

[ghorrocks]

I appears you want to mesh the blades with turbogrid. In that case import the mesh into ICEM and then you can edit the mesh in there and split the surface into two. You might need to move some nodes around to do this accurately.

[Julian121]

Can someone please post steps needed to split a generated mesh on a surface using in ICEM?
Mesh has been generated by Turbogrid.
I have not been able to find any tutorial on this.

[ghorrocks]

In ICEM you can select surface elements (which are your boundaries) and change which part they belong to. So you can generate a new part and individually select which surface elements you want to change into another part. You will then probably have to put a curve on the boundary and move the nearby nodes so they lie on the boundary curve.

Sorry, but I am not going to give you more of a tutorial than that. You are going to have to do the ICEM tutorials available on the ANSYS Customer webpage and/or academic site and learn the package. Also the ICEM documentation is worth reading as ICEM is totally different to any other ANSYS you have used. You should also open up a few test meshes and just play around until you get the hang of changing part names and editing meshes.