[kasoya]

This question is about multi-domain. It seems that in my PW project, the connector between domains can not be processed by Fluent correctly.

I randomly created two .pw files and did almost the same operations, finally exported the .cas files. It's confusing that the normal.cas can be read by Fluent normally, while the abnormal.cas can not, saying "no face with given nodes". I'm wondering if anyone would point out what's wrong with that "abnormal.pw".

note:
1. I don't think this problem is about orientation, i understand the "i j k" issue.
2. If the inner connector is manually set to a unspecified boundary condition, then it can be read by Fluent without that error. But Fluent will recognize it as "wall". In fact, I really need it to be "interior".

[kasoya]

(for 2D situation only). So it is about orientation...

1.choose the structured domains, make sure "i j k" right;

2.choose the unstructured domains, EDIT-ORIENT-NORMAL-APPLY-OK;

3.export and try.

Btw, how to check the orientation of an unstructured domain???

[dgarlisch]

This is a common problem when building 2D grids!

In abnormal.pw, the "z" normals of the two domains are not aligned. For Fluent export to work properly, they must be pointing in the same direction.

You can view and change a domain's orientation by selecting the domains and choosing Edit > Orient....

HOWEVER, the domain types (Str, Uns) must be the same when choosing multiple entities. So in your case, you can only orient them one at a time.

[kasoya]

Originally Posted by dgarlisch

This is a common problem when building 2D grids!
In abnormal.pw, the "z" normals of the two domains are not aligned. For Fluent export to work properly, they must be pointing in the same direction.
You can view and change a domain's orientation by selecting the domains and choosing Edit > Orient....
HOWEVER, the domain types (Str, Uns) must be the same when choosing multiple entities. So in your case, you can only orient them one at a time.

Dear dgarlisch,
Thanks for your help. Still, there is another question.

For domains of Str type make sure "I-right, J-up" then it will be ok.

But for domains of Uns type, no matter how many times I click the "normal" and "apply" button, those tiny red marks, which i think are used to tell the "z" normal of this Uns domain, never change. Then how do i know which direction its z normal is pointing?

[dgarlisch]

You need to rotate the view away from looking "straight down" on the domains. Then you will be able to see the direction of the normal arrows.

To rotate the view, hold down the Ctrl-key (on winOS and linux) or Cmd-key (on MacOS) while dragging the right mouse button.

[kasoya]

Originally Posted by dgarlisch

You need to rotate the view away from looking "straight down" on the domains. Then you will be able to see the direction of the normal arrows.

To rotate the view, hold down the Ctrl-key (on winOS and linux) or Cmd-key (on MacOS) while dragging the right mouse button.

wow..how interesting! I never thought it would be this way. Thank you so much~