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[surface handling] SurfaceFeatureExtractConvert

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Old   January 25, 2009, 05:28
Default SurfaceFeatureExtractConvert
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Fabian Braennstroem
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Hi,

I wonder, if anybody uses surfaceFeatureExtract and -Convert and more interesting for which kind of problems!? For me it looks, that surfaceFeatureExtract could create the needed eMesh file for snappyHex's featureEdge refinement...which does not work somehow!?
So maybe surfaceFeatureConvert is the needed tool to create eMesh, but this needs a nastran formated file...

The format of the surfaceFeatureExtract file looks like for a simple cube with includedAngle 91:

{
externalStart 0;
internalStart 15;
featureEdges 36 ( 2 8 11 24 28 32 40 46 53 56 65 83 85 94 96 139 168 172 197 215 224 227 261 267 268 290 308 314 327 366 369 399 406 411 443 448 );
featurePoints 1 ( 184 );
}
In addition there are some .obj files created!?

Would be nice, if anyone has some suggestions!

Greetings!
Fabian
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Old   February 11, 2009, 05:28
Default The features section in snappy
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Mattijs Janssens
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The features section in snappyHexMeshDict is a way to add refinement without using the automatic feature detection ('resolveFeatureAngle').

Currently the only ways to get these eMesh files:
- create them by hand
- convert them from a suitable line format (Nastran is so far the only format)

There is currently no way to extract them from a surface (that would be equivalent to using the resolveFeatureAngle anyway).

Attached a modified tutorial case where it adds refinement on the edges of one of the blocks.

You'll also see the limitation - since the features get refined first there is no cell to pick up all the corners of the block and it misses some of the edges. It should do a better job on larger scale features.


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Old   February 11, 2009, 14:24
Default Hi Mattijs, thanks for the
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Fabian Braennstroem
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Hi Mattijs,

thanks for the info! Would you upload the modified again? I will take a look at the nastran eMesh files. Maybe, one can get some feature snapping by using surfaceFind and some points movement...

Fabian
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Old   February 11, 2009, 14:26
Default Hi Mattijs, thanks for the
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Fabian Braennstroem
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Hi Mattijs,

thanks for the info! Would you upload the modified again? I will take a look at the nastran eMesh files. Maybe, one can get some feature snapping by using surfaceFind and some points movement...

Fabian
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Old   March 15, 2010, 04:01
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BastiL
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Quote:
Originally Posted by braennstroem View Post
Maybe, one can get some feature snapping by using surfaceFind and some points movement...
Fabian,

did you succed to get some feature snapping with this? Thanks.

Regards Bastian
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