Learning Forum

[Webster]

Hello community,

When I was running a FSI simulation (Transient Structural and Fluent), the following error message were echoed from Transient Structural module:

===========================================================  

*** ERROR ***                           CP =   67653.844   TIME= 08:21:24
 There is not enough memory for the Distributed Sparse Matrix Solver to  
 proceed.  This error has occurred on the process with MPI Rank ID = 10  
 on machine (ce-bg112).  Please increase the virtual memory on your      
 system and/or increase the work space memory and rerun the solver.      
 The memory currently allocated by this process = 376 GB.  The memory    
 allocation attempted = 0 GB.  The largest block of memory allocated by  
 this process that is available for the Distributed Sparse Matrix        
 Solver = 0 GB.

===========================================================                                                         

A few facts:

• I believe I have prescribed sufficient constraints to my model, and I attemped to reduce the number of elements. 
• There is no problem when running structural analysis alone.
• The error message could raise at any points during my simulations (e.g., 36%, 41%, 50%) - seems that it is just random, but I cannot say this for certain.

I was confused by the memory of 376 GB allocated to the process - how can this be possible?  Thanks.

[dlooman]

Are you using parallel processing with a large number of processors?  It sounds like memory used for previous iterations is not being released.

[Webster]

Thank you for your reply. I am using 20 cores on a single local workstation. And yes, it looks like the momory from the previous iterations is buffered somewhere, could you please suggest me how to give a fix? Thanks.

[Gary_S]

Unreasonable memory allocations are because the model is moving in space. It may also be rotating or oscillating. 
Add additional supports or suppress parts until you find the issue.