FEM meshing doesn't generate volume elements

About the development of the FEM module/workbench.

Moderator: bernd

nquantum
Posts: 22
Joined: Fri Aug 03, 2018 1:29 am

Re: FEM meshing doesn't generate volume elements

Postby nquantum » Sat Sep 08, 2018 4:45 pm

Since this is not really related to the topic from the first post and the topic was years old, I made an own topic.
Yes I'm hesitate to open new topic also I think it relate to original topic that why I post here in the beginning. If you think I should post on new topic just tell me ok?
The question is, what exactly would you like to analyze?
I'm designing CNC I want to see how strong the X-base like previous picture. How much it sag from the total weight of y-axis, z-axis? So I determine lower weight or use bigger/smaller aluminum extrusion and/or aluminum plate. Also want to see see weak point of structure so I can move some part here and there to balance or stronger the weak point. I've also have picture of my design here which... have problem of self-intersect , so I cannot do analysis on FEM.

Also :
I recreate file and track down where cause of self-intersect mesh using Gmsh in FEM.
Those bearing block which have hole-trough on top of round-rail create self-intersect. Those two I use fuse union before meshing. If I use intersect those two there is something left! Which should not have since the hole is 10mm radius, rail also 10mm radius. Maybe this is the cause?

If I use simple solid rectangle instead of those hole-trough bearing and fuse union with same round-rail, then no problem of self-intersect.

Back to original question.
- meshing in FEM how to fix self-intersect?
- how to avoid?
- how self-intersect happen? I try to search in forum, there is no clear answer.

Or any suggestion is welcome.
Thank
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linear wit block3
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linear wit block2
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linear wit block1
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b.jpg
cnc design
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faq1.FCStd
recreate file
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nquantum
Posts: 22
Joined: Fri Aug 03, 2018 1:29 am

Re: FEM meshing doesn't generate volume elements

Postby nquantum » Sat Sep 08, 2018 4:47 pm

And intersect , rail , block
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block
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linear rail
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linear and block
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4.jpg
intersect
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nquantum
Posts: 22
Joined: Fri Aug 03, 2018 1:29 am

Re: FEM meshing doesn't generate volume elements

Postby nquantum » Sun Sep 09, 2018 5:10 am

Maybe part go trough another part can cause problem also?
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c.jpg
cnc
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