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Old   March 13, 2009, 00:13
Default distorted elements! Still trying to figure out...
  #1
Faraaz
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Hi guys,

I am getting these errors so many times. I still does not fully understand it. The error message is "One or more elements have become highly distorted....". What does it really mean, what are the possible causes and solutions to that problem?

Any help, advice would greatly be appreciated. I need to really figure this out to be able to continue with my work.

Thanks Faraaz.
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Old   March 13, 2009, 00:43
Default Re: distorted elements! Still trying to figure out
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Rikio
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Faraaz,

Have you checked the quality of your mesh? Maybe you can find them out because of high distortion.

Rikio
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Old   March 13, 2009, 10:14
Default Re: distorted elements! Still trying to figure out
  #3
Faraaz
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Hi Rikio, Do you mean that i should be able to see the distortion bit? Well i could see like a hole in the mesh, looking like a small triangle, then i coarsened the mesh a little bit and it disappeared. Then my simulation worked. But I needed finer mesh to get accurate results and refined it even more. Now i cannot see anything like distortion in the mesh but I am getting that error message.

I am sorry if this seems like stupid but I am just a beginner.

Thanks Faraaz
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Old   March 13, 2009, 10:34
Default Re: distorted elements! Still trying to figure out
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Rikio
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Faraaz,

It seems that it is caused by the low quality of mesh. Does the quality reach 0.2 or beyond?

Rikio
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Old   March 13, 2009, 10:44
Default Re: distorted elements! Still trying to figure out
  #5
Faraaz
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Where should I check if the quality is 0.2 or beyond? I will check it and get back to you later. By the way, I am using CFX-Mesh to mesh my geometry.

Thanks
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Old   March 13, 2009, 10:54
Default Re: distorted elements! Still trying to figure out
  #6
neewbie
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You can view your mesh in CFX Post.

Check for the angles (Maximum Face Angle/ Ortho.Angel) as the mesh is "distorted", which means small/bad angles.

Are there any inflationlayers involved?

neewbie
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Old   March 13, 2009, 12:41
Default Re: distorted elements! Still trying to figure out
  #7
Faraaz
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Hi neewbie, My min face angle is 4.2. Max face angle is 164. Max edge length ratio is 203. Max element volume ratio is 85.

According to CFX help my mesh is not very good. from cfx help it is not good if: Edge Length Ratio > 100 Max Face Angle > 170˚ Min Face Angle < 10˚ Element Volume Ratio > 5

This means that I have to improve my mesh quality. And yes there are 25 inflation layers and am not sure how many layers am supposed to use and what it depends on. Could you give me some advice on how to improve the mesh.

Thanks very much. Faraaz
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Old   March 16, 2009, 11:14
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  #8
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Matthias Vo
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sorry.
ive got problems with the reg.
you might have to check your minimum face/body spacing... reduce it so it fits your last prismlayer ratio.
or setup a face spacing on the faces of the inflation and let it have a radius of influence higher then your inflationboundary.
hope that helps.

neewbie
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Old   March 17, 2009, 11:32
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Faraaz
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Hi, I got problems too with the reg.
I will check the things you told me about and I will let you know what happens.

Thanks
Faraaz.
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