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90 degrees pipe bend - changing shape midway

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Old   May 20, 2010, 11:25
Default 90 degrees pipe bend - changing shape midway
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Dear foamers,
I have created a bend in blockMesh using the O-grid technique (squared center section). However, when investigating the 3D geometry in paraView, the mid pipe profile (45 degrees) of the bend is not quite circular. I have looked over the arc section in blockMeshDict over and over again, but I cannot find any obvious errors. It this how it is supposed to be, or should I file a bug report?
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Old   May 25, 2010, 02:29
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Lachlan Graham
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Hi,
I have had a similar experience with a pipe bend geometry, I could not find anything to explain it.
I used Solidworks to check the numbers used on the arcs, could not fix the problem.
Lachlan
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Old   May 25, 2010, 04:16
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Good. A temporary solution in blockMesh may be to create pipe bend in increments of, say ~40 degrees. Apart from that, an external mesh/geometry seems to be the only way out at the moment.

I have now also filed a "bug report" using a 179.9 degree bend (-> blockMesh pipe shape not preserved in bend).
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Old   May 25, 2010, 20:07
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Many thanks for that. I was also going to try the simple if tedious option of increments. I will also have a go with ExtrudeMesh as in the bug report.
Regards,
Lachlan
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