Learning Forum

[nirvana]

Hello, I've got the following error while running a non linear static structural analysis:The L-2 norm of the residual force overflowed. This may be caused by  n PRED,ON or birth/dead elements. Please use PRED,OFF and try again.   n  >>> DOF LIMIT EXCEEDED. MAX VALUE= 0.000000   LIMIT= 0.000000  nI've noticed that the force is very large compared with the force convergence criterion, however I don't understand what the error mean. Do you know how to fix it?nI didn' use any birth death elements.nThanksn

[Aniket]

Are you using student software or any other license? when do you get this error? What is the DOF count of your model? Search for the Number of Equations in the solver output file to find total DOF in the model. Also what is node and element count? I am asking this because it may have to do with the limitations of student software.n-AniketnHow to access Ansys help linksnGuidelines for Posting on Ansys Learning Forumn

[Ashish Khemka]

nnSometimes predictor does hurt convergence. Try turning it off. Simply insert a command object in the analysis object in the model tree, and type in 'pred, off'.nnRegards,nAshish Khemkan

[nirvana]

Hi,nMy licence id not student, so I don't think it is a problem of nodes count. I've edited the model since I've noticed that the shared topology to get a conformal mesh didn't work well for two bodies, thus I think it was a problem of contact and rigid body motion, in fact by running a modal analysis 3 modes were zero, this means a bad contact, right? However the model had about the following featuresnThe force was very large compared with the criterion.nIf I replace the shared topology with a bonded contact things work.nThanksnn