Vechile Body FEM Model 1

[burtek]

Hi all,

I have just started to structural analysis of vechile body and I need some advices
I have only a cad-geometry of the body before welding process therefore all the parts have the fillet area and most of the parts don`t contact each other. If I use this cad-geometry, unfortunately FEM software gives an Error in meshing process.
I think the simple way in order to overcome meshing problem; to hide all fillet process and to provide the connection of parts in cad-geometry.
My questions:
1- Is there another way without any change in cad-geometry?
2- How is the process of vechile body structure analysis in industry? e.g. is another suitable cad-gometry used?

Thanks in advance

 

[GregLocock]

I don't know the exact details but at least one manufacturer prepares a list of all the spotwelds and then uses a macro to stitch the model together at those points, using a proprietary model of a spotweld.

What element size are you using?



Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[burtek]

Hi Greg,

thanks,
element size is over 1000.
I tried to stitch a small group of parts of the vehicle body and analysed it but for the whole body it will takes too much time and i dont know the macro:-(

Regards

 

[GregLocock]

How big is a typical element in mm?



Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[burtek]

if I dont misunderstant, you want to know the size of vechile body:

2570mm width,
3225mm hight,
6530mm length,

or
and if you can please tell me what you think, I can give more helpful information

Regards

 

[GregLocock]

I need to know the size of a typical element. Or else post a picture of the mesh that you are using.



Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[burtek]

it gives an error during mesh generation, therefore there is no Element :-(

 

[GregLocock]

Well then we are at something of an impasse.



Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[burtek]

what can you advice about vehicle body structure analyses (generally speaking)? can you please tell me a hint, literature, sample or whatever which will be help me about this subject? I have just started and you know that everything is very hard in the beginning:-(

Regards

 

[GregLocock]

OK, how proficient are you at FEA in general, rather than just vehicle structures?

What is your FEA model for?


Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[burtek]

I m new in industry. I have some FEM experiences and what I learned in my education.
I must obtain deformation and stress distribution under static loadind for new design of the vechile body.

Regards

 

[drmuh]

Hi,
I would not go with auto meshing if this is a full vehicle. Actually I never recomment auto mesh unless you have a very good CAD at hand. Some geometries may not be perfect and your mesh will end up with missing parts, interfering parts etc. You can generate a weld file or a connector file for your weld locations and then realize the connectors to end up with any type of joint including spot weld - RBE2, ACM2 etc. Usually, spot welds are defined in CAD geometry and you can generate a macro (get support from your pre-processing software company at least)for fast realization of connectors. It is a very long story, but my recommendation is keep away from auto meshing especially if you are new to the industry. If timing is an issue, automesh partially. Midsurface generation may end up in a failure with poor CAD data.
Take care,
Mert

http://www.novosim.com

Product Development Services (cad/cae/test)
Medical Device R&D

 

[rizwan696]

in ansys how to troubleshoot
when working in workbench i get an error ansyswb module has stopped working !!
everytime i try opening anything this error pops up please help if anyone has had the same error before

 

[pgpada]

From what i understand that he sais he is propably using Catia FEA. it only gives these two things.
And also the dimensions for the element are taken from the geometry and so most of the times really huge.
I think putting the geometry on Ansys Workbench should be the solution because it defines contacts by itself.
But this is not the correct solution.


PGP