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Help understanding-->fieldOutputs['S'].values has two different results for each element

Help understanding-->fieldOutputs['S'].values has two different results for each element

Help understanding-->fieldOutputs['S'].values has two different results for each element

(OP)
I'm trying to report the von Mises stress at specific location on my model (3D-shells with S4R elements). To that end, I partitioned the locations of interest into small squares, and seeded the edges of those partitions such that there will always be only one element in the partition. Then, I assign the faces of the partitions into individual geometry sets (thus creating elements sets as well). I run the analysis, and extract the stress with the following python script (not showing the import commands, etc., to save space)

-----------------------------------------------------------------------------
sets=['S02-01','S02-14','S02-15','S02-16','S02-17','S02-44'] #project specific location names

lastFrame = odb.steps[steps[0]].frames[-1]

stress=lastFrame.fieldOutputs['S']

for setNumber in range(0,len(sets)):
--location=odb.rootAssembly.elementSets[sets[setNumber]]
--locationStress=stress.getSubset(region=location)
--locationValues=locationStress.values
--for v in locationValues:
-----print sets[setNumber], v.elementLabel v.mises
-----------------------------------------------------------------------------

the results printed are as follows (first column is the set ID, second column element Label, third column Stress of interest)

ElementSet, ElementID, VonMises Stress
S02-01, 3, 2.59445095062256
S02-01, 3, 2.74841952323914
S02-14, 1983, 6.80963182449341
S02-14, 1983, 6.42978477478027
S02-15, 5, 3.05168008804321
S02-15, 5, 3.25940418243408
S02-16, 111, 2.47030067443848
S02-16, 111, 2.63920927047729
S02-17, 1776, 2.61065101623535
S02-17, 1776, 2.23680400848389
S02-44, 11, 2.12529110908508
S02-44, 11, 2.19687485694885
-----------------------------------------------------------------------------------

As seen, there are two different values for the von Mises stress at each element. The first value reported is what is seen using the 'Query-probe value' tool in the GUI. Anyone know what the second value is reporting? There is only one step in this model.

After investigating further, there are two separate fieldOutput['S'].values objects... that is, there is a fieldOutput['S'].value[0] and fieldOutput['S'].value[1]

Any insight is greatly appreciated.

RE: Help understanding-->fieldOutputs['S'].values has two different results for each element

S4R has one integration point and by default (Simpson integration) 5 section points through thickness. By default A/Standard writes the results of the 2 outer section points into the .odb.

RE: Help understanding-->fieldOutputs['S'].values has two different results for each element

(OP)
Ahh! That makes sense. I think either of those outputs are acceptable for my purpose (mesh convergence study). For future reference, are you aware of how to force output of all five section points? I can't find an option in "Field Output Requests".

Thanks again!

RE: Help understanding-->fieldOutputs['S'].values has two different results for each element

You can get output at all points with:

*ELEMENT OUTPUT, ELSET=SetName, VARIABLE=ALL
1,2,3,4,5

RE: Help understanding-->fieldOutputs['S'].values has two different results for each element

(OP)
I see... if I'm correct, I think this will do the same in the GUI, then, right?

RE: Help understanding-->fieldOutputs['S'].values has two different results for each element

That'd be my guess, but I generally don't spend much time in the GUI except for results visualization/post-processing. You can verify in the .inp after writing it from the GUI though.

RE: Help understanding-->fieldOutputs['S'].values has two different results for each element

(OP)
Yeah, it looks like it did it. Here's an image for anyone else's future reference.

Thanks for your help!

RE: Help understanding-->fieldOutputs['S'].values has two different results for each element

Yes, it's the same option.

In /CAE it is easy to have a preview at the input file. Model -> Edit Keywords

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