FEA analysis of a tube frame
FEA analysis of a tube frame
(OP)
Hi, I am just starting using SW 06 and am having some problems with modeling and analysis of a spaceframe construction for the car I am making.. as I want to model it in SW and analyse its torsional stiffness properties...
now, the easiest way for me is to use a 3D sketch and make my tube frame, then use the weld profiles tool and assign each section of the sketch with a tube.
now, when I do the analysis in COSMOS it doesn't understand that the tubes are actually connected togeather, so there are two ways of doing it, that I see:
1. use fillet welds and weld the tubes in SW
2. use the restraint tool in COSMOS and "tell" cosmos that the tubes are rigidly connected in the frame..
the first solution doesn't always work, in fact once I have a real 3D spaceframe, where I have joints wit several tubes going in, the SW fillet weld feature just will not weld some tubes togeather...
the second solution is very time consuming, and makes COSMOS block and crash from time to time...
I have also tried exchanging the tubes in the model with solid bars of equal cross section area (as I presume that tension/compression of the tube swill have much greater influence on the frame torsional stiffness than tubing bending) but that does make it much faster but the problems persist...
does anyone use SW to model tube frames and analyse it's properties... care to share some tips? or should I look for other software...?
best regards
vlado
now, the easiest way for me is to use a 3D sketch and make my tube frame, then use the weld profiles tool and assign each section of the sketch with a tube.
now, when I do the analysis in COSMOS it doesn't understand that the tubes are actually connected togeather, so there are two ways of doing it, that I see:
1. use fillet welds and weld the tubes in SW
2. use the restraint tool in COSMOS and "tell" cosmos that the tubes are rigidly connected in the frame..
the first solution doesn't always work, in fact once I have a real 3D spaceframe, where I have joints wit several tubes going in, the SW fillet weld feature just will not weld some tubes togeather...
the second solution is very time consuming, and makes COSMOS block and crash from time to time...
I have also tried exchanging the tubes in the model with solid bars of equal cross section area (as I presume that tension/compression of the tube swill have much greater influence on the frame torsional stiffness than tubing bending) but that does make it much faster but the problems persist...
does anyone use SW to model tube frames and analyse it's properties... care to share some tips? or should I look for other software...?
best regards
vlado






RE: FEA analysis of a tube frame
I'm not sure how accurate you'll need the analysis to be, but one thing you can do is save your assembly/part as a part and then join the various bodies. Run the analysis on the part file with the joined bodies. This won't take into account weld strength, so may not be quite what you're looking for.
Jeff Mowry
www.industrialdesignhaus.com
Reason trumps all. And awe trumps reason.
RE: FEA analysis of a tube frame
Best Regards,
Heckler
Sr. Mechanical Engineer
SW2005 SP 5.0 & Pro/E 2001
Dell Precision 370
P4 3.6 GHz, 1GB RAM
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RE: FEA analysis of a tube frame
I am using full COSMOS... by the way..
as for my understanding of FEA, well, I understand the physics of it, as I had it in my lectures some time ago while I was studying... hell, I could even do the calculation for my tube frame by hand, but I need to experiment with my design a bit (optimize the various tubing thickness/diameters) so I need a relatively fast tool..
I did some experimental models, very simple spaceframe structures, and I noticed some problems that SW had with displacement plots, especially on the load points... will look into this..
cheers
vlado
RE: FEA analysis of a tube frame
RE: FEA analysis of a tube frame
cheers
vlado