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Hi all,

I´m running a "big" 300,000 element model in parallel processing of a topographic mesh containing a dam and tailings. At this point I´m setting the gravitational forces using UCSD NDmaterial in elastic stage. Everything runs smoothly and result has been checked using Flac3D.

When everything works, I have roller in all four boundary sides of the model and pinned based. Two sides of the model are aligned with X direction, they are parallel and are the same, with equal number of nodes. The same applies for Y direction. If I run the model having the X direction with Equal DOF in the boundary sides, the models doesn´t run. It gets stuck before showing any iteration.

I´m only changing the boundary conditions for X direction, nothing else. The model doesn´t show any error, just get stuck.

Finally, I tried using different constraint options, such as Penalty, Transformation and Plain.

Saludos,

Alfredo

can you elaborate some more on what you mean by stuck. thanks.

ps. if you don't have a 1 flag at end of test, put it there and see if any stuff comes to the screen.

Hi Frank,

I already have a flag in the test options, thus is showing all the info. By stuck, I mean it doesn´t reach the iteration process, thus there is nothing to show.

Anyway, we figured out the problem. EDOF needs the master and the slave nodes to be in the same processor, otherwise it get stuck looking for one or the other. Now it runs, but we are afraid if we divide the project in more pieces (larger number of processors) we will end up separating master and slave nodes.

Do you have any comments on this matter? We need to come up with a solution for using more processors.

Saludos,

Alfredo

so you were using MP .. SP should handle the constraints properly (if it can handle the element and material types you are using) .. if you can send me a small script has the same hang up issue i will try and modify the code to at least spit out an error message.