RAM usage 1

[yaston4]

Hi, is there anyway to force abaqus to use more RAM during the analysis. The total amount I state in the job module never seems to get used during the analysis. Just wondered if there was a way to make abaqus use all the ram I state to speed up the run times.

Thanks.

 

[burningDiesel]

Why should more RAM use speed up run times?
The model (i.e. stiffness matrix) just gets loaded into the RAM, and that's about it. Bigger model, more RAM use.
Thinking about it, that's more than likely why abq/STD uses more RAM than EXPL, as calculating the inverse matrix is very memory intensive.

Anyway, your question doesn't make much sense.

 

[IceBreakerSours]

You can not "force" ABAQUS to use more RAM. You might be able to reduce the convergence time by using more CPUs on your machine as follows:

abaqus job=myINP cpus=# memory=$$$$mb interactive

myINP: Name of your INP.
#: Number of CPUs.
$$$$: Amount of memory (4000, for example)

If you are running Standard, more/faster memory will help. If you are running Explicit, faster/more processors will help.

Even in case of Standard, the processors may not run at near full capacity at all times. Same is true for memory.

Another perspective: If possible, avoid nonlinearities as much as you can. Depending on the problem, you may try using reduced integration elements, exploit symmetry, and use simplified geometry.

http://www.eng-tips.com/faqs.cfm?fid=376

 

[yaston4]

Yes, sorry your are correct, the run times do not speed up with more RAM, but more RAM will be able to process more complex models. My problem involves contact and that's where the problem is I believe. The model has about 7 million DOF, and 16GB RAM is not enough for this. I am using Incompatible mode elements, I will try Reduced Integration elements to see if this helps.

Any other ideas are much appreciated!

Thanks