extracting material properties from Abaqus

[markor99]

Thank You for new version. I'm new here and not familiared with python, so please be emollient...
I'm trying to extract material properties from Abaqus 6.13.1 and have a problem. All steps listed below:

1. Built plain weave fabric and matrix domain - entered properties of fibres and matrix
2. Exported model to Abaqus voxel file.
3. Edited .inp file in Notepad - added manually shear modulus of matrix (as i can see this option is still not available from interface). Please look at the picture below. Added value of shear modulus marked by red ellipse.

1.matrix G.jpg (80.27 KiB) Viewed 22661 times

4. Files .inp, .ori and .eld have been copied to Abaqus working folder
5. Activated Abaqus from command window: abaqus job=k49ve
6. Abaqus started process and generated numerous files in working folder.
7. Closed Abaqus and copied files "dataHandling.py" and "effectiveMatPropRVE.py" to Abaqus working folder
8. Edited "effectiveMatPropRVE.py" file in Notepad as showns picture below - changed FileName for "k49ve" and value of TM to "1". Changes marked by red ellipse

2.script edit.jpg (90.95 KiB) Viewed 22661 times

9. Activated Abaqus and opened .odb file and then ran scripts, previously copied to working folder.
- run "dataHandling.py" - nothing happen
- run "effectiveMatPropRVE.py" - errors appear as shows attachment below:

3.abaqus error.jpg (147.4 KiB) Viewed 22656 times

Will be very appreciated for information, what did wrong and suggestion how to solve it.

Regards JK

[louisepb]

Hi JK,

Abaqus assumes a shear modulus of E/2(1 + v) for isotropic materials which is why this is not entered explicitly in the .inp file generated by TexGen.

There seems to be a problem with the thermomechanical step in the .inp file. I thought that I had solved this but it seems to have resurfaced (presumably for a different reason). If you run the script with TM=0 it should generate the mechanical properties without problems. If, however, you want to output the CTE's then I don't have a solution at the moment. I will try and work out what the problem is and get back to you.

Sorry not to have a full answer but I hope that helps in the first instance,
Best regards,
Louise

[markor99]

I've done all as per Your suggestions:
- I did not add shear modulus in .inp file
- TM=0

Unfortunatelly result is similar - script dataHandling.py doesn't work, script effectiveMatPropRVE.py makes similar error as shown below.

error.jpg (37.61 KiB) Viewed 22634 times

Regards
JK

[louisepb]

Hi,

In that case try removing the thermomechanical step from the inp file, making sure that you don't leave an extra line at the bottom.

Best regards,
Louise

[markor99]

Hi

Thermomechanical removed from the .inp file, with no extra line on the bottom, then repeated all steps. Nothing changed - exactly same contents of Abaqus error window as attached in previous post.


Regards
JK

[louisepb]

Hi JK,

In that case could you send me the Abaqus input files and the tg3 file so that I can try and work out what's going on. The model I tried worked fine without the thermomechanical step so maybe it's something specific to your model.

Best regards,
Louise

[markor99]

Hallo

Attached .tg3 file. Couldn't upload .inp file as its size exceed limit.

regards
JK

[louisepb]

Hi JK,

I have created a .inp file from your model using 50x50x20 voxels. It works fine in Abaqus 6.14-1 with the thermomechanical step taken out. Please could you let me know how many voxels you used so that I can try and replicate your problem. You could send me your .inp file via Dropbox if you have an account.

I will have to investigate the issue with the thermomechanical step.

One thing I did notice with your model is that TexGen gives errors because the volume fraction is unrealistic (typically 1.45). Are you sure you have input your yarn properties correctly? Your model looks like the default 2x2 plain weave so are the fibres per yarn, linear density etc correct for this?

Best regards,
Louise

[markor99]

Hallo

Abaqus Voxel files have been created as shown below:

voxel.jpg (22.65 KiB) Viewed 22598 times

I've made some mistake in yarn properties, which caused unrealistic volume fraction - already corrected

Link to my .inp file:

https://www.dropbox.com/s/9ihreaj0e493f ... e.inp?dl=0

Regards
JK

[louisepb]

Hi JK,

The .inp file doesn't seem to correspond with the model that you sent. The x range on the model is -0.5 to 1.5. In the .inp file it is -0.715 to 2.145.

Please could you send a complete set of matching inp, ori, eld and tg3 files which I can use to try and see what the problem is?

Thanks,
Louise

[markor99]

Hallo

Link to all requested files:
https://www.dropbox.com/s/599vdblkrjq90 ... e.zip?dl=0

Additionally to my previous information - Abaqus crashes few minutes after loading .odb file, showing following window:

abaqus crash.jpg (54.67 KiB) Viewed 22591 times

Regards
JK

[louisepb]

Hi JK,

I've tried both the Abaqus file you sent and ones generated from your model and they both work fine with Abaqus 6.14-1 on my machine. If I change line 24 in effectiveMatPropRVE to TM=1 then I get the error you describe. Are you sure you've changed this to 0? If you have then I'm mystified. There is a problem with the thermomechanical step which I will investigate (may take me a while as the colleague who wrote the script has now left and I'm not an Abaqus expert) but it should work fine if you take this out.

Let me know how you get on.
Best regards,
Louise

[markor99]

All is working now, thank You.
Abaqus gives me elastic properties of lamina: E, v and G in three directions.
Is there any way to get the strength properties as well?

Best regards
JK

[maryam_sodagar]

Dear Louise

Hi
Thank you for the time you are sharing with us.
1.When I import .inp (dry fibre) from abaqus, the .eld and .ori files are not included in .inp file? I mean we should do something else to export orientations and material properties to abaqus separately?
2.How can I assign the yarn properties (or the information in .eld and .ori files) in .inp file manually? Would you please copy and paste a sample in .inp file in which these properties have been assigned manually? Because I am not expert enough to use these scripts.
3.and when I calculate the volume fraction, where should I use it? I do not know if it is useful or not.
I am so sorry for disturbing you.
Thank you,

[maryam_sodagar]

Dear Louise

I know you are so busy but I really need you or anybody else to answer to these questions.
If anybody know, please help me solve these problems.
Thank you so much,