An Unknown Error in 2-way FSI

[hjun401]

Hi, I'm trying to simulate 2-way FSI of pulsatile flow in an elastic tube with Ansys 2021 R1 provided by college. During the simulation, it stopped  at 74%(it took almost a week) with these errors.
(DP 0) An unknown error occurred during solution. Check the Solver Output on the Solution Information object for possible causes.
(DP 0) A solver failure occurred during the run in the Transient Structural system.
So, I checked the file0.err and found this error
CP =  147786.438   TIME= 04:19:38
An unexpected error has occurred on MPI rank 0 in the MPI software used
by Distributed ANSYS.  Distributed ANSYS is unable to recover and will
terminate.  Please send the data leading to this operation to your
technical support provider, as this will allow ANSYS, Inc to improve
the program.
Can anyone explain how can I prevent these errors? Thanks.
ps. I use Intel i7-6700K(4 cores), 32GB of memory, no GPUs. License is provided by university IP(FlexNet?).

[Federico]

Hello, 

I would suggest that you check the transcripts from each participants (.trn for Fluent, .out for Mechanical) and to find more specific information as to what may have cause this issue.