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Li July 31, 2008 11:22

minus volume mesh in ICEM
Hi everyone,

I am meshing a tube shown in this website, 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!


Rogerio Fernandes Brito July 31, 2008 17:31

Re: minus volume mesh in ICEM
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?

sivaramakrishnaiah August 1, 2008 00:05

Re: minus volume mesh in ICEM
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 maintain good elements(as per standared of skew angle). please tell me your model size and element size.

Li August 1, 2008 02:32

Re: minus volume mesh in ICEM
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

Rogerio Fernandes Brito August 1, 2008 08:58

Re: minus volume mesh in ICEM
Could you show for us?

My e-mail is:

myron August 1, 2008 10:11

Re: minus volume mesh in ICEM
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.

Li August 3, 2008 04:56

Re: minus volume mesh in ICEM
Hi myron, thank you. I will try.

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