Reply To: Simulation getting diverged after 149000 iterations

[Stephen Orlando]

hi Please provide some images showing the geometry, expected motion, Fluent and Mechanical meshes.
When running System Coupling and it stops running, the first thing to do is examine the output files for each solver to look for clues to what happened. For Fluent, look at the transcript .trn file. For Mechanical, look at the .out file. Also, look at the System Coupling log file, .scl. You can also try re-running the case and stopping it just before the timestep when it crashes, then examine the mesh in Fluent or CFD-Post to get more clues.
It is very important to build up the FSI simulation in stages as opposed to setting up the 2-way FSI right at the start. This document "Best Practices for Coupled Fluid-Structure Interaction (FSI)" describes this process and is available here: https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v211/en/sysc_ug/sysc_bestpractices_fsi.html
System Coupling User's Guide \\ Best Practices for System Coupling \\ Best Practices for Coupled Fluid-Structure Interaction (FSI)
Steve