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minus volume mesh in ICEM

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Old   July 31, 2008, 11:22
Default minus volume mesh in ICEM
  #1
Li
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Hi everyone,

I am meshing a tube shown in this website, http://img124.imageshack.us/my.php?image=tubeid3.png I always got minus volume close to the expansion and decreasing area. I am using Ogrid block along the tube length. Would you give me any hints to improve the mesh quality? Thank you very much!

Li
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Old   July 31, 2008, 17:31
Default Re: minus volume mesh in ICEM
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Rogerio Fernandes Brito
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Increase the number of elements near this region! Divide the block near this region! Close to the expansion, are you using an o-grid mesh?
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Old   August 1, 2008, 00:05
Default Re: minus volume mesh in ICEM
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sivaramakrishnaiah
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mr.Rogerio Fernandes Brito,is telling correct and another method is there and decrese mesh element size,correction factor,first remove bad elements(choose skew angle) in case skew angle is not as per standared value.to maintain good elements(as per standared of skew angle). please tell me your model size and element size.
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Old   August 1, 2008, 02:32
Default Re: minus volume mesh in ICEM
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Li
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Thank you for the response! I get the o-grid along the length first and then I split at two bigger circle side and get three block. The tube sizes are D200 and D300, the height of the first grid close to the tube wall is 1mm, and global maximum size is 20mm. Thanks!

Regards, Li
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Old   August 1, 2008, 08:58
Default Re: minus volume mesh in ICEM
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Rogerio Fernandes Brito
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Could you show for us?

My e-mail is: rogeriobrito2007@hotmail.com
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Old   August 1, 2008, 10:11
Default Re: minus volume mesh in ICEM
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myron
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My guess is you need to move the block vertices from the O-grids near the locations where the diameters change. Move those vertices so they're a little into the largest diameter rather than going straight across the diameter. This will correct the bad angles where the contraction occurs.
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Old   August 3, 2008, 04:56
Default Re: minus volume mesh in ICEM
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Li
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Hi myron, thank you. I will try.
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