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[nirvana]

Hi,

I'm trying to run a simulation but after some minutes I get the following error "Insufficient memory was available for the solver engine to obtain a solution.  Try simplifying the model to reduce problem size.  Please see the Troubleshooting section of the ANSYS Workbench Help System for more information"

The solver output provides this information

actually this error occurred after I unchecked the box "Distribute Solution if Possibile" in Solve Process Settings of Mechanical. Before doing that I had got the same error but after1 hour of simulation.

The pc I'm using has a RAM of 64 Gb, the hard disk where is my model is 464 Gb. 

In the WB Mechanical APDL settings under Tools I can see that database memory is 1024 Mb and Workspace memory 2048 Mb and processors are set to 2.

While in the Mechanical settings of my model under Tools- Solve Process Settings there are 4 max number of cores.

How can I overcome these problems without reducing the mesh quality of my model? 

Thanks for the attention.

[Aniket]

As the error message states, you need 84 GB RAM to solve this problem.

You can either:

• reduce the node count in the mesh using larger mesh size


• Increase virtual memory of your machine


• switch to iterative solver. For this your RAM requirements will be reduced and HDD requirement will increase, also it will be slower than the direct solver that you are trying to user right now.

-Aniket

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[nirvana]

Hi, thanks for your reply,. However I can see from the advance settings of the performance of the pc that the available virtual memory in the disk I'm using is 472087 MB should I increase it? Up to what amount?

Thanks

[Aniket]

This allocation seems excessive for given physical memory.

Google max virtual memory allocation and you'll see multiple threads like this:

https://www.tomshardware.com/news/how-to-manage-virtual-memory-pagefile-windows-10,36929.html

So only option that you can use now is to use the iterative solver.

-Aniket

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[nirvana]

actually iterative doesn't works too and if I increase the mesh size I get a lots of error related to intersecting meshes or failure for some bodies. If I use a smaller size everything is ok, nut elements are very very high in number and I got those problems.

[Aniket]

you will need to simplify the geometry before coarsening the mesh then, and what error do you get with the iterative solver?

[nirvana]

I get this error using iterative solver. 

Actually I find it quite strange since some time ago I ran a simulation with an element number higher than the one which few days ago gave me this problem of memory, and that time it worked without problems. Now it seems that is is not allowed.

[Aniket]

so error seems to have increased the requirement for iterative solver as compared to the direct solver are you sure that mesh is exactly the same in these cases?

In any way coarsning the mesh or using a larger physical RAM machine seems only option now.

-Aniket

Guidelines on the Student Community

How to access ANSYS help links

[nirvana]

just this question then I can close this discussion. What do you mean by simplifying the geometry? Do you refer to the usage of simmetry?

[Aniket]

Yes, if possible use symmetry.

You mentioned Nuts, if they are hexagonal with the actual fillets, they tend to have large mesh concentration. Check the parts that are not essential or can be simplified. For example, an actual nut with threads can be simplified to a cylinder with a cylindrical hole in it if it is not in area of interest.

 

[nirvana]

ok thanks!