[ICEM] Multizone meshing Problem for External Flow Meshing

Hybrid · March 19, 2013, 10:24

Hi,

i am trying to mesh on a fin-body configuration using multizone option in ICEM 14.5, facing problem while filling the 2D block to 3D fill.

The geometry consists of body+fins (360 deg no symmetry) and a farfield (cylinder). The body is enclosed in the farfield surface (no contact between the body and farfield). The material point is defined between the body and farfield.

2D surface block initialized very well. When I tried to fill it with Multizone with advanced filling option, volume filled the farfield ignoring the body.

No volume mesh, why?

Anybody can help me?

Its an external flow problem.

PSYMN · March 20, 2013, 09:51

at the moment, 2D to 3D fill only works if the faces are all connected. It will not support this situation where there is no contact between the FF and the body.

You could try creating a symmetry model (the symmetry plane could connect the FF and Body) and then mirror it if you need a full model.

Hybrid · March 24, 2013, 13:10

It works really great with a half mesh.

The problem arises at the sharp trailing edge of the airfoils, a very low quality mesh Quality is around 0. in that areas.

How can I handle that while working in multizone meshing?

PSYMN · March 25, 2013, 09:26

Maybe a picture of the problem would help.

Hybrid · March 28, 2013, 12:30

here are a pic and project file attached.

PSYMN · March 28, 2013, 14:07

In your case, you had very high aspect ratio quads... I didn't even see a volume mesh, but if you had generated one, the pyramids against those quads would have been even worse...

How about a nice MultiZone swept mesh instead?

Something like this (the CYAN mesh is a cutplane thru a swept quad dominant MZ mesh).

MZ_Wing.jpg

I attached a blocking file. Let me know if I have permission to post a tutorial on this model and I will make a 1 minute demo to show you how it is done.

Best regards,

Simon

PSYMN · March 28, 2013, 14:08

I should note that for the best quality mesh, I would recommend a hexa blocking... But the MultiZone Mesh can be done without any blocking skills...

Hybrid · March 28, 2013, 16:36

Error in opening Blocking File. Better to add geometry as well.

You can post the tutorial privately if not possible to post here.

Hybrid · March 28, 2013, 16:42

Prisms not there, what happened with quality when prism layers will present?

can this technique be used for complex configurations like whole aircraft with control surfaces etc ?

Quote:

Originally Posted by PSYMN

How about a nice MultiZone swept mesh instead?

Something like this (the CYAN mesh is a cutplane thru a swept quad dominant MZ mesh).

Attachment 20225

Simon

cfd seeker · March 29, 2013, 09:24

Quote:

Originally Posted by PSYMN

In your case, you had very high aspect ratio quads... I didn't even see a volume mesh, but if you had generated one, the pyramids against those quads would have been even worse...

How about a nice MultiZone swept mesh instead?

Something like this (the CYAN mesh is a cutplane thru a swept quad dominant MZ mesh).

Attachment 20225

I attached a blocking file. Let me know if I have permission to post a tutorial on this model and I will make a 1 minute demo to show you how it is done.

Best regards,

Simon

Quote:

Let me know if I have permission to post a tutorial on this model and I will make a 1 minute demo to show you how it is done

That would be great help to us. I always come across issues while dealing with Multizone rather never had a success with it

March 19, 2013, 10:24	Multizone meshing Problem for External Flow Meshing	#1
Hybrid Senior Member Ali Join Date: Jan 2012 Location: Pakistan Posts: 134 Rep Power: 16	Hi, i am trying to mesh on a fin-body configuration using multizone option in ICEM 14.5, facing problem while filling the 2D block to 3D fill. The geometry consists of body+fins (360 deg no symmetry) and a farfield (cylinder). The body is enclosed in the farfield surface (no contact between the body and farfield). The material point is defined between the body and farfield. 2D surface block initialized very well. When I tried to fill it with Multizone with advanced filling option, volume filled the farfield ignoring the body. No volume mesh, why? Anybody can help me? Its an external flow problem. __________________ Best Regards Ali Last edited by Hybrid; March 19, 2013 at 10:27. Reason: To edit title, subject heading

March 20, 2013, 09:51		#2
PSYMN Senior Member Simon Pereira Join Date: Mar 2009 Location: Ann Arbor, MI Posts: 2,663 Blog Entries: 1 Rep Power: 47	at the moment, 2D to 3D fill only works if the faces are all connected. It will not support this situation where there is no contact between the FF and the body. You could try creating a symmetry model (the symmetry plane could connect the FF and Body) and then mirror it if you need a full model. Far likes this. __________________ ----------------------------------------- Please help guide development at ANSYS by filling in these surveys Public ANSYS ICEM CFD Users Survey This second one is more general (Gambit, TGrid and ANSYS Meshing users welcome)... CFD Online Users Survey

March 24, 2013, 13:10		#3
Hybrid Senior Member Ali Join Date: Jan 2012 Location: Pakistan Posts: 134 Rep Power: 16	It works really great with a half mesh. The problem arises at the sharp trailing edge of the airfoils, a very low quality mesh Quality is around 0. in that areas. How can I handle that while working in multizone meshing? __________________ Best Regards Ali

March 25, 2013, 09:26		#4
PSYMN Senior Member Simon Pereira Join Date: Mar 2009 Location: Ann Arbor, MI Posts: 2,663 Blog Entries: 1 Rep Power: 47	Maybe a picture of the problem would help. __________________ ----------------------------------------- Please help guide development at ANSYS by filling in these surveys Public ANSYS ICEM CFD Users Survey This second one is more general (Gambit, TGrid and ANSYS Meshing users welcome)... CFD Online Users Survey

March 28, 2013, 14:08		#7
PSYMN Senior Member Simon Pereira Join Date: Mar 2009 Location: Ann Arbor, MI Posts: 2,663 Blog Entries: 1 Rep Power: 47	I should note that for the best quality mesh, I would recommend a hexa blocking... But the MultiZone Mesh can be done without any blocking skills... __________________ ----------------------------------------- Please help guide development at ANSYS by filling in these surveys Public ANSYS ICEM CFD Users Survey This second one is more general (Gambit, TGrid and ANSYS Meshing users welcome)... CFD Online Users Survey

March 28, 2013, 16:36		#8
Hybrid Senior Member Ali Join Date: Jan 2012 Location: Pakistan Posts: 134 Rep Power: 16	Error in opening Blocking File. Better to add geometry as well. You can post the tutorial privately if not possible to post here. __________________ Best Regards Ali

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