An exclusive raffle opportunity for active members like you! Complete your profile, answer questions and get your first accepted badge to enter the raffle.
Hello,
I am trying to do an encasing simulation but every time i launch optistruct, I am getting this error (ERROR #941); I tried changing the magnitude of the translation but it still doesn't work. Please help.
Thank you
Hi @KBE
Could you please share the model file, please to find the reasons for non-convergence.
Hi Prakash,
Due to the company confidential policy, I can not send you the file. However, I can tell you that I am try to encase two cylinders. See below for the config details:
Contact Group:
- DISCRET : S2S
- TRACK = CONSLI
- Property ID = PCONT
PCONT details:
- STIFF = SOFT
- MU1 OPTIONS = REAL VALUE
MU1 = 0.13
- SEPARATION = YES
- FRICESL_opts -- ticked
After changing some things around, below is the current message I am getting.
* Friction or STICK can cause more difficult nonlinear convergence - if feasible try frictionless gap/contact. * This problem has gap elements with friction or stick condition. For more intuitive results and often better convergence, set GAPOFFS on GAPPRM card to AUTO. (This may violate rigid body balance, especially for unsupported structures.) * This problem has elasto-plastic materials and the maximum plastic strain 1.10e+002 is beyond the limit of small deformation theory. This may be the cause of non-convergence. Using fully integrated plastic elements may improve convergence, although possibly create overly stiff results.
I look forward to your advice
Hi KBE,
Do you expect large/finite sliding interactions between the cylinders? If not, please change the TRACK field to SMALL.
Also, add the below PARAM card and see if that helps
PARAM,EXPERTNL,CNTSTB
Thanks
Vikas
Hi KBE, Do you expect large/finite sliding interactions between the cylinders? If not, please change the TRACK field to SMALL. Also, add the below PARAM card and see if that helps PARAM,EXPERTNL,CNTSTB Thanks Vikas
Hi Vikas,
thank you but that wasnt the problem. I already had PARAM, EXPERTNL and CNTSTB defined. I dont remember what it wad but I changed something in the PCONT card and it worked. I think i already posted my solution.
Thanks again
-KBE
Hey All;
I had the same error : OptiStruct thinks that a contact problem, but I found that stiffness matrix (MAT9) is not stable ... and that's why the solver didn't converge.
Best regards,
