structural simulation with contact

[pizzaf40]

Hello, everyone!
I'm new here.

I wanted to learn how to make non-linear simulations with contact between solid elements surfaces.
I did (as usual) an apdl to be able in a short time to change the geometry and variables of the model. I tried to create a contact couple conceptually similar to that of the tutorial in the help.

result...the iterations of newton raphson do not converge (divert, and tend to diverge less to the increase of the normal penalty stiffness factor)...every tot iterations of nr does a bisection, with which more or less halves the residual. only that at the tenth bisection it blocks everything and ansys declares the non convergence of the system.

the explanation of the model can not do it exactly, but I can post the apdl...just make file->read input from and select the file.txt... is attached!

thank you for any help!

 

[Mattia_v]

hello pitu, but what do you use for contact? What do you think? I recommend that you pass to an augmented lagrange that contains a constant term for contact pressure and is a little better (what kind of contact you use, for epserienza I tell you that the frictionless and the rough are those that on leave to treat better body frictional I tried to use a couple of times but it turns you crazy) for the application of the load you must avoid as the plague the bisezioni because they stretch of a life the calculation and after a while they block it, then start with a small fraction of the load (say from one fifth to one tenth). I usually use workbench and therefore are not very practical of how you impose everything in classic ansys unfortunately. . .

 

[pizzaf40]

muaffmuaff:d ciao vendra!
I've spent a bit of time on something else. Now I have read, but I admit that I will see it later because now it is not wessential but sooner or later I have to learn it. for now I have found a remotely acceptable method to create acceptable pressure distribution remaining in the linear.. I've got some time, but I'm starting to try everything! ...and maybe you ask for some attention to set the apdl properly.

following the convergence on the flight during the resolution, for absurd it seemed that n-r did not converge, every tot iterations of n-r made a bisection and the residual halved! but my problem is definitely upstream, i.e. the settings that do not bring me n-r converge

for the fact "wb vs. normal", if you know how to get back to the command name, then we are interfaced with great ease!

in case you feel for cell! the sprizzetto is always around the corner :d

 

[LA LU]

Hello I read your post! for the university I am simulating something similar with the non-linear procedure with contact surfaces.
Did you solve it for iterations?

Thank you.