Partitions with same section results in stress discontinuities at the interface
Partitions with same section results in stress discontinuities at the interface
(OP)
As the title explains, in my abaqus model I've a part that is split in two regions by a partition. For each region I've defined the same section separately (i.e. I've assigned an "A" section to the first region, and then the same "A" section to the other region). The analysis shows a gap in the stress (mises) field and I really can't explain why. The section (so the material) is the same, the regions have the same finite element mesh, so no discontinuities can be justified. Is this a solver issue or it's my fault in modelling the element? Is there any workaround?
If assign the section at the same time to both the regions abaqus shows no discontinuities.
Thanks.
If assign the section at the same time to both the regions abaqus shows no discontinuities.
Thanks.





RE: Partitions with same section results in stress discontinuities at the interface
If you the same material defined and no change in mesh in those two regions, then why did you create a partition in the first place?
Do you care about the stress discontinuity near the partition? Isn't it far enough from the location of contact?
If you do care about it, how significant is the discontinuity compared to average values in the neighborhood of the discontinuity?
Finally, have you made sure there is no change in element formulations in the two regions?
http://www.eng-tips.com/faqs.cfm?fid=376
RE: Partitions with same section results in stress discontinuities at the interface
RE: Partitions with same section results in stress discontinuities at the interface
b) If they are, try refining the mesh.
http://www.eng-tips.com/faqs.cfm?fid=376
RE: Partitions with same section results in stress discontinuities at the interface
RE: Partitions with same section results in stress discontinuities at the interface
http://www.eng-tips.com/faqs.cfm?fid=376
RE: Partitions with same section results in stress discontinuities at the interface
Download Link .cae
If you try to run the analysis you will see some warnings that can be ignored (like a null density warning: I've defined the mass of the impacting mass using the engineering features and so I've set 0 density in the material properties),
ps. If I remove the partition there is no more a gap in the stress field. But I need that partition.
RE: Partitions with same section results in stress discontinuities at the interface
http://www.eng-tips.com/faqs.cfm?fid=376
RE: Partitions with same section results in stress discontinuities at the interface
RE: Partitions with same section results in stress discontinuities at the interface
http://www.eng-tips.com/faqs.cfm?fid=376
RE: Partitions with same section results in stress discontinuities at the interface
RE: Partitions with same section results in stress discontinuities at the interface
Abaqus CAE User's Manual section 42.5.2 (for v6.11):
"Abaqus/CAE averages values at nodes common to two or more elements when the contributing elements lie in the same result region. The default result regions are the same regions defined when you assign sections to your model; you can also define custom result regions using saved element sets or display groups. You can choose whether or not Abaqus/CAE averages values at nodes common to two or more result regions. You can suppress averaging across regions (use the region boundaries) to emphasize any discontinuities at region boundaries, or you can request averaging across regions (ignore region boundaries) to produce a more continuous effect."
~!ce.
http://www.eng-tips.com/faqs.cfm?fid=376
RE: Partitions with same section results in stress discontinuities at the interface
The fact is that I can't explain why a partitioning automatically produces a discontinuity in stress field. It should not happen if I assign to both regions the same section-material.
If you've seen my .cae file, have you any idea of what can give such a behaviour?
RE: Partitions with same section results in stress discontinuities at the interface
I'm analysing what you've suggested. I'll report back here once I've investigated. Thanks a lot for your efforts.
RE: Partitions with same section results in stress discontinuities at the interface
Thanks a lot. That was the reason.
Turning off "use region boundaries", under "computation" tab in "result options" window, has done the trick.
Really thanks for sharing your knowledge and time.
I wish you a good day.