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Internal error in boundary respecting

NaveenKumar Honnagondanahalli
Hi all i am working on fuel cell. i did a cell model with one side open and other side closed .
the fuel is passed from the closed side.

The problem is while i am going to mesh it itz showing " error : Internal error in boundary respecting in subdomain 1 " plz guide me what is this error asap.

i am using comsol 3.4 version.

8 Replies Last Post 11 Mar 2015 12:30 GMT-04:00
Posted: 8 years ago 30 Oct 2009 03:02 GMT-04:00
Hi
from my experience, such erros arrive when I have poorly defined my geometry, or imported it from programs that are not clean in the way they close the poly-lines defining superiour geometries, this often happens for dxf file format. I would recheck my geometry, and use the "repare" and or "defeaturing search", I suppose its already there in V3.4
Good luck
Ivar
Hi from my experience, such erros arrive when I have poorly defined my geometry, or imported it from programs that are not clean in the way they close the poly-lines defining superiour geometries, this often happens for dxf file format. I would recheck my geometry, and use the "repare" and or "defeaturing search", I suppose its already there in V3.4 Good luck Ivar

Posted: 5 years ago 26 Jul 2012 12:28 GMT-04:00
Hi,

I'm working on a geometry and I got such an error right now.
I did repair as you said, but it did not work. It gave me such an error:

"Failed to respect boundary element edge on geometry face."
one boundary couldn't be meshed with the remaining geometry.
Why that can be happening?


thanks

--
physics undergrad
loves photon.
Hi, I'm working on a geometry and I got such an error right now. I did repair as you said, but it did not work. It gave me such an error: "Failed to respect boundary element edge on geometry face." one boundary couldn't be meshed with the remaining geometry. Why that can be happening? thanks -- physics undergrad loves photon.

Posted: 5 years ago 26 Jul 2012 17:12 GMT-04:00
Hi

probably you have very small/short lines, or small sharp faces that implies very small mesh elements, or the repair did not work properly

--
Good luck
Ivar
Hi probably you have very small/short lines, or small sharp faces that implies very small mesh elements, or the repair did not work properly -- Good luck Ivar

Posted: 5 years ago 27 Jul 2012 06:54 GMT-04:00
It's so abnormal that the program gives such an error, since I have such 8 boundaries, but it gives an error about only one of them. Mesh looks like in the picture. It shows the problematic boundary.

how I created the geometry:
after creating two cylinders and one sphere, I intersected one cylinder one sphere with keeping input objects, so I created middle domains that are created by the intersection. Then I used delete entities to delete the remaining parts of the cylinder.
The result is one sphere with two caps at opposite ends.

--
physics undergrad
loves photon.
It's so abnormal that the program gives such an error, since I have such 8 boundaries, but it gives an error about only one of them. Mesh looks like in the picture. It shows the problematic boundary. how I created the geometry: after creating two cylinders and one sphere, I intersected one cylinder one sphere with keeping input objects, so I created middle domains that are created by the intersection. Then I used delete entities to delete the remaining parts of the cylinder. The result is one sphere with two caps at opposite ends. -- physics undergrad loves photon.


Posted: 5 years ago 5 Sep 2012 08:16 GMT-04:00
when such an mesh related error occurs increasing the mesh quality from normal to fine or finer often helps but also increases calculation time a lot... in the ideal case you would only increase the quality in the problematic area - if u can find it
when such an mesh related error occurs increasing the mesh quality from normal to fine or finer often helps but also increases calculation time a lot... in the ideal case you would only increase the quality in the problematic area - if u can find it

Posted: 5 years ago 5 Sep 2012 16:14 GMT-04:00
Hi

my experience is that you should then identify where the mesh issue is and adapt the mesh manually to start to make some local entities with a finer mesh and leave the global "normal" mesh to avoid that you increase the mesh density everywhere.

But mesh density is your discretisation, so once you have solved, you shoul always check the gradients of your solutions, do you have several elements across anny steep gradient ? if not here you shoul densify locally your mesh

--
Good luck
Ivar
Hi my experience is that you should then identify where the mesh issue is and adapt the mesh manually to start to make some local entities with a finer mesh and leave the global "normal" mesh to avoid that you increase the mesh density everywhere. But mesh density is your discretisation, so once you have solved, you shoul always check the gradients of your solutions, do you have several elements across anny steep gradient ? if not here you shoul densify locally your mesh -- Good luck Ivar

Karan Bikkannavar
Posted: 3 years ago 12 Jun 2014 16:31 GMT-04:00
Hello

I am trying to mesh the geometry as shown in the attachment. It has a thickness of about 0.05inches.
I tried to mesh using most of the mesh options available in 4.3a version, but still the error persists.

May I please know how to work on the problem?

Hello I am trying to mesh the geometry as shown in the attachment. It has a thickness of about 0.05inches. I tried to mesh using most of the mesh options available in 4.3a version, but still the error persists. May I please know how to work on the problem?


Andrew Kiernan
Posted: 3 years ago 11 Mar 2015 12:30 GMT-04:00
I am aware this reply is late but if anyone else comes to this thread for advice on meshing,

I would have used a free triangular mesh on the arc then swept through the rest of the domain with a distribution and finally used a converted to change the squares created by the swept mesh into triangles.

Andy
I am aware this reply is late but if anyone else comes to this thread for advice on meshing, I would have used a free triangular mesh on the arc then swept through the rest of the domain with a distribution and finally used a converted to change the squares created by the swept mesh into triangles. Andy

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