Tips on simple 2D contact model

[bigphikl]

Hi,

I am quite new to abaqus, and am more familiar with finite volume methods.
I am trying to create a 2D contact problem in abaqus (see attached pic).

I am putting a uniform pressure on the top surface of the hemicircle and am constraining the bottom of the brick.

I have ran a few different models with different mesh types and size and different contact types, mainly with the explicit solver.

I have trouble getting the standard solver to run, if i try make the mesh finer, which solver would be more suitable for my case? i am not particularly interested in the dynamic response, just the steady state stresses.

Secondly, i define a contact pair between the curved edge of the hemicircle and the top of the brick, i have trouble in some cases where the hemicircle isnt constrained and just flies off. Should i be constraining the model in some other way? I have tried putting a tie constraint between the two surfaces and the job solves but Im not sure if the accuracy of the results are affected.

I know this is a long post but basically, i am just trying to find out the right way to set up such a model.

Btw both parts are steel.

Any help would be much appreciated,
Philip.

 

[rstupplebeen]

First, I did not open the file but I think you need to add stabilization in the contact properties or the step definition. If you search in this forum for stabilization I think you will find some more detailed posts about this. I hope this helps.

Rob Stupplebeen

 

[Nileo2005]

Explicit is your best bet for this problem; don't even worry about standard here, because theres only going to be one solution for this problem anyway. You need standard when things can start moving and collapsing in different directions. At lest thats what my experience has taught me.
And as tge flying away part, just add a little friction in the contact surface. Make the contact "Rough". So slipping then.

 

[Noirom84]

Hi!
Try to use enchanced hourglass control in mesh control. Avoid triangle elements in cylinder discretization. In contact properties use hard contact.
Use direct contact specyfication (in hard contact properties), unless you have convergency problems, then use penalty method.
In contact interaction properties use surface to surface option.

Regards