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Mechanica results are way off

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hygear

Mechanical
Joined
Apr 15, 2011
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50
Location
US
I'm working on an FEA for a steel structure made from 2"x2"x3/16" structural tubing. This is a follow up to an FEA I ran several months ago before I made some modifications to my structure. The new FEA is being done under WF 4.0 and the old FEA was done under WF 2.0. For some unknown reason, my stresses are approximately the same but my displacements are about 1000x what they should be in the new FEA. For the load that I have applied I would expect about 9mm of displacement but I am getting 9500mm. I have triple checked the units and everything is right, but the numbers are wrong.

Anyone ever seen this happen before?
 
I found the problem...

Looks like some of the materials in our material library have the incorrect units. I redefined the material in my model and now the numbers make sense again.
 
An interesting lesson here! These days, analysis codes are all pretty robust and do exactly as you tell them. The problem is nearly every case is with the inputs...
 
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