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sasanghomi March 13, 2013 08:26

Creat a Patch with zero size
Dear foamers ,

I want to creat a patch with zero size in the boundary file...
I know that creatPatch utility doesnt do it...

any utility??:confused:

Thanks and best regards ,

aljazari March 13, 2013 09:33


Here's an example of an empty patch in the boundary file:


type patch;
nFaces 0;
startFace 306310;
type patch;
nFaces 67;
startFace 306310;
The wall is empty, no cells or anything.

sasanghomi March 13, 2013 10:03

Hi Abdulhaq ,

thanks for your reply ,
But I want to know how can I creat this patch?
I think adding this patch manually in the boundary file is wrong because I dont know anythings about startFace....
correct me if I am wrong...


aljazari March 13, 2013 10:46

If you notice the start face for the inlet is the same as the empty patch (wall), so just take the starting face for any patch.

cutter March 13, 2013 12:04

Why do you want to create an empty patch anyway?

mturcios777 March 13, 2013 12:28

You need empty patches for the attachDetach modifier, so that's one usage. Just remember to update the number of patches at the top of your boundary file, otherwise your solver will crash.

Also, it seems safest to add empty patches at the start of your boundary file, in my experience.

sasanghomi March 13, 2013 16:59

Dear Marco,

Thank you very much.
your guess is correct I want it for attachDetach modifier :D
I got it.

thanks ,

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