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-   -   distorted elements! Still trying to figure out... (https://www.cfd-online.com/Forums/cfx/27138-distorted-elements-still-trying-figure-out.html)

Faraaz March 12, 2009 23:13

distorted elements! Still trying to figure out...
 
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.

Rikio March 12, 2009 23:43

Re: distorted elements! Still trying to figure out
 
Faraaz,

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

Rikio

Faraaz March 13, 2009 09:14

Re: distorted elements! Still trying to figure out
 
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

Rikio March 13, 2009 09:34

Re: distorted elements! Still trying to figure out
 
Faraaz,

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

Rikio

Faraaz March 13, 2009 09:44

Re: distorted elements! Still trying to figure out
 
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

neewbie March 13, 2009 09:54

Re: distorted elements! Still trying to figure out
 
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

Faraaz March 13, 2009 11:41

Re: distorted elements! Still trying to figure out
 
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 > 170Ëš Min Face Angle < 10Ëš 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

mvoss March 16, 2009 10:14

sorry.
i´ve 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

cfxuser1 March 17, 2009 10:32

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.

TRIGUI October 26, 2016 06:08

hi,
please how can i see the distortion bit in ansys Mesh ?
Thanks for help


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