Challenges reading from ODB

[moose613]

Hi,

I am relatively new to using python with Abaqus, typically I will use the CAE GUI.

I am doing a large number of models, and need to use scripting to output E33 strain at unique nodes along a line.
In each model, there is a nodeset that contains the nodes along the line, and this nodeset is found in odb.rootAssembly.nodeSets['example_nodeset_name']

I would like the Z-coordinate and E33 strain written to an output file, for each node in the nodeset.

This is what I have so far:

strains = frame.fieldOutputs['E']
nodes = odb.rootAssembly.nodeSets['example_nodeset_name']
strain_at_nodes= strains.getSubset(region=nodes, position=NODAL)

outputFile = open('example_file_name.txt','w')
for k in range(len(strain_at_nodes)):
outputFile.write((strain_at_nodes[k]))
outputFile.close()


I know this doesnt work, but it should give an idea of what I am trying to achieve.
Any ideas as to how achieve my objectives would be greatly appreciated.

Cheers,

Moose

 

[testing]

Having done something similar with nodal displacements, off the top of my head, my code reads something like this (along with the odb opening and such)

topnodes=odb.rootAssembly.instances['InstanceName'].nodeSets['NSETTOP']
results=odb.steps.values()[-1].frames[-1] # References the last frame of the last step
defs=results.fieldOutputs['U].getSubset(region=topnodes)

 

[moose613]

Thats essentially what I have so far,but I am having problems.

so far:

step1 = odb.steps['Step-1']
frame = step1.frames[-1]
strains = frame.fieldOutputs['E']
nodes = odb.rootAssembly.nodeSets['example_nodeset_name']
strain_at_nodes= strains.getSubset(region=nodes, position=NODAL)

How can I output E33, node label, and z coordinate to an output file?

Thanks in advance

 

[testing]

I create a list to store what I want to write to file, then use numpy.savetxt to write it to the file.

 

[moose613]

So it seems that there arent any strain values saved for unique node locations.

Can anyone confirm whether is is possible to request nodal strains from abaqus, or do I need to get the strain at the integration points and then convert that to unique nodal?

 

[csk62]

I typically used the strain averaged at the nodes option when I write the strain values to a (.fil) file. If not, then I think you might have to use the integration points and then unravel it all later.