[ANSYS Meshing] Sweep mesh results in extreme aspect ratio

Highflower · January 11, 2016, 09:32

Hello,
I have a problem when I use sweep mesh. I have a rather complex geometry consisting of 2252 bodies (sliced to be sweepable).
The final mesh consists of ~4.5 million cells with mostly really good quality cells.
In order to use inflations on all surfaces I use surface inflation and manual source selection. When I sweep the bodies the mesh turns and twist a little even though the source and target is identical and the path between them is strait (I hope you understand what I mean even if I might not use the right terminology...

)
This is hardly visible in each sweep but since the geometry is sliced in MANY different bodies (in the sweep direction), each specified with one sweep method, the distortion results in extremely high aspect ratio in some cells (~1e20) in the bodies far from the first source.

Top mesh, good quality

Distorted mesh in lower layer, bad quality

As you can see the mesh is very different in these two layers even though they are swept from the same surface. The encircled areas are where the aspect ratio is getting extreme..

I assume there is an easy solution to this problem, I have searched but not found anything..

Must be possible to somehow specify that the mesh should be identical on the source and target. Grateful for any tips!

Thanks in advance!
Best regards
Olle

Kapi · January 11, 2016, 23:19

have you tried to give edge sizing in all the bodies shown?
Try to give edge sizing and put behavior as "hard"

Cheers
KAPI

Highflower · January 12, 2016, 09:44

Thanks Kapi for your reply!

I have now specified edge sizing on all the bodies, a lot of manual work..

I thought it was not possible to specify anything on the lower faces since they should use the mesh from the target face of the previous one.. However, it seems I was wrong about that..

It is now regenerating the mesh and it seems to work fine, will come back with the results of the finished mesh!

Highflower · January 12, 2016, 12:59

Thanks again!
It all worked out fine! Perfect mesh through the whole geometry!

Best regards
Olle

Kapi · January 12, 2016, 17:40

happy that it worked for ya!

look into doing some scripting if you do this on regular basis and have lot many bodies to deal with.

Cheers
KAPI

January 11, 2016, 09:32	Sweep mesh results in extreme aspect ratio	#1
Highflower New Member Olle Högblom Join Date: Jan 2011 Posts: 5 Rep Power: 15	Hello, I have a problem when I use sweep mesh. I have a rather complex geometry consisting of 2252 bodies (sliced to be sweepable). The final mesh consists of ~4.5 million cells with mostly really good quality cells. In order to use inflations on all surfaces I use surface inflation and manual source selection. When I sweep the bodies the mesh turns and twist a little even though the source and target is identical and the path between them is strait (I hope you understand what I mean even if I might not use the right terminology... ) This is hardly visible in each sweep but since the geometry is sliced in MANY different bodies (in the sweep direction), each specified with one sweep method, the distortion results in extremely high aspect ratio in some cells (~1e20) in the bodies far from the first source. Top mesh, good quality Distorted mesh in lower layer, bad quality As you can see the mesh is very different in these two layers even though they are swept from the same surface. The encircled areas are where the aspect ratio is getting extreme.. I assume there is an easy solution to this problem, I have searched but not found anything.. Must be possible to somehow specify that the mesh should be identical on the source and target. Grateful for any tips! Thanks in advance! Best regards Olle

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January 11, 2016, 23:19		#2
Kapi Senior Member Join Date: Apr 2014 Location: Melbourne Posts: 584 Rep Power: 14	have you tried to give edge sizing in all the bodies shown? Try to give edge sizing and put behavior as "hard" Cheers KAPI

January 12, 2016, 09:44		#3
Highflower New Member Olle Högblom Join Date: Jan 2011 Posts: 5 Rep Power: 15	Thanks Kapi for your reply! I have now specified edge sizing on all the bodies, a lot of manual work.. I thought it was not possible to specify anything on the lower faces since they should use the mesh from the target face of the previous one.. However, it seems I was wrong about that.. It is now regenerating the mesh and it seems to work fine, will come back with the results of the finished mesh!

January 12, 2016, 12:59		#4
Highflower New Member Olle Högblom Join Date: Jan 2011 Posts: 5 Rep Power: 15	Thanks again! It all worked out fine! Perfect mesh through the whole geometry! Best regards Olle

January 12, 2016, 17:40		#5
Kapi Senior Member Join Date: Apr 2014 Location: Melbourne Posts: 584 Rep Power: 14	happy that it worked for ya! look into doing some scripting if you do this on regular basis and have lot many bodies to deal with. Cheers KAPI