I do not believe the fixture is the same. You might want to split the flat faces and add fixtures on a small area of them.
Nice validation case! Pretty close. I think if you can match the way the load and restraints are applied you can get a bit closer but over all things are pretty close. Can you post your simulation results and file to see if there is anything else that can be adjusted. I think the restraint might not perfectly match like Alin suggested, but matching the way the load is applied will be hard. Maybe add one more part to get the motion exact or play with the material properties in the assumption they aren't perfect.
I don't think splitting the shell face and adding a fixed restraint on a flat face vs the straight edge
should make any difference -- the first 'column' of shell elements can't move (no trans or rot) --
but I can give it a try.
Though I think everyone would agree that you should never mess with a model thats giving
you the answer you want.
I did try a force based analysis.. non linear / following force -- but I couldn't get the model
to deform correctly. And solution time took at least 10X that of displacement based.
I've attached my model and CWR file as a single ZIP if anyone is curious.
Jared -- not sure I follow about adding an addition part. I certainly could tweak mat'l props to get
the same exact answer -- but 1) that'd be cheating, no? and 2) i don't know the exact material of
the ruler -- it just says "stainless" on it. Nonetheless, any stainless will be about the same
result +/-10% probably.
I'd just like to verify that my assumptions (about stress being meaningless but reaction force
being correct) are true. IE me and Simulation are making the same assumptions. And I'm not
just fooling myself with a lucky hit.
Again, any insight, greatly appreciated.
simulation sample - ruler.zip 10.0 MB
I don't think I understand why you don't trust the stress. The displacement, shape and reaction forces are what you expect, why wouldn't the stress be valid? Those are pretty good validations, the only other way to check would be a hand calc, but you've done better through physical testing.
The reason I suggested a different pulling method is because based on the description of your setup, the displacement around an axis, I would expect a perfectly circular bend. In your real test you're pulling on it and restraining it slightly differently. The only way to get an exact match is with an exact setup.
Overall, you could say you got lucky with the setup, but everything points to a valid analysis as far as I can see. You could throw some strain gauges on maybe for another validation point I guess, but I think you're good.