The Model with NLGEOM never converges in spite of hugly relaxing the convergence criterion and applying artifical damping to the model to supress the instability.
How to solve this convergence problem
Thanks mrgoldthorpe
I am glad that finally someone got me
I am doing staged construction ( height increases with time) of an embankment. Layer 2 is the foundation on which the embankment of differnt layers to be built (Layer 1 , layer 3 ..and so on). Yes I need NLGEOM becuase the materials are...
My humble understanding is that "tie constraint" implies rigid interface [full binding] between the two surfaces in which must be in full contact with each other.
Therfore "tie constraint" is a special cas of "tied contact pair formulation" in which the interface between the two surfaces (may...
mrgoldthorpe thanks for your time and help
In your reply
http://www.eng-tips.com/viewthread.cfm?qid=132367
1-You seemed to define the Surf-1 (of part-1)consisting of several edges and Surf-2 (of part-2) consisting of different edges in CAE at Assembly level.as these two surfaces coincide(no...
hamadadf
have you done staged construction through ABAQUS before, if yes i just want to double-check if Surfaces and Tie Constraint must be used to tie interface elements of the deactivated layer with the activated one being deformed so that the whole deactivated layer moves as a rigid body...
Dear bfillery
Partition does not help as the partitioning line will not be recognized by ABAQUS as a surface.According to my humble understanding , only the border lines of a part are recognized as a surfaces the surface, unless you know a way of transferring the partitioning lines to surfaces...
I have built my model using one part only. However, i realize that I need to use Constraint (Tie) which (i believe) only binds two surfaces from two different parts, so I need to divide the part I built into different parts.
Can that be done,..? or I should recreat the model from the begining...
Thanks mrgoldthorpe.
Just more Idea about my problem so that you may be able to help me overcome 2 weeks of disappointing solution attempts.
My problem seems similar to the one you have referred me to
(staged layers construction) so I built the whole model (in ONE PART ONLY)first and then...
Documentation says about Model Change: "Element removal/reactivation can be used only in general analysis steps"
However , I am puzzeled if
Model Change , Add (or Remove Element)
can be inserted within a Geostatic , Soils Steps . or one should perform the model change (ADD or Remove) under...
Thanks xerf. You are right... after careful looking at the Doc, *Equation must be introduced in the part or assembly edits , which means that it will be operated throughout the whole analysis. I am thinking of a solution to this issue.
I am applying Displacement BC throughc the contraints option
*Equations
However I need this to be applied only in a specific Step where in the following steps this Contraints should be eliminated.
Upon runing the analysis I got message :
"Error in job : in keyword *EQUATION, line 1402: The...
zekeman,
Well the idea of trying to get T given in an analytical formula is because I am going to use it in another close formula. Plus you talk about developing numerical solution as if it were piece of cake and requires few minutes to finish without any troubles.
P.S. I have no intention now...
let me tell what I am doing regading this issue so that we can share knowledge. As you know that the nonlinear equation is d^2T/d^2x=C*dT/dt
and the nasty C(T) =(dS/dT) * T + S + A(dS/dT). Now if the relation between S and T is emperical (fitting curve),why not find S=f(T) for which
(dS/dT)...
