Systems

Systems

Bubble dynamics simulation in FSI problems

    • Z_Heidary
      Subscriber

      I want to do a transient FSI simulation to investigate the effect of an elastic tube conveying fluid on an oscillating bubble inside the tube.

    • Stephen Orlando
      Ansys Employee

      Do you get the same error with this tutorial? https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v221/en/sysc_tut/sysc_tut_reedvalve_fluent.html. Are you running on a local machine or trying to run on a remote machine?
      Steve
    • Z_Heidary
      Subscriber
      Hi Steve,
      Thanks for your reply.
      No, I did not get this error with the mentioned tutorial. I'm using a remote machine to run this simulation since my local machine does not have enough RAM.
    • Stephen Orlando
      Ansys Employee
      Please describe in detail how you're submitting the job to the remote machine.
    • Z_Heidary
      Subscriber
      I use "Remote Desktop Connection" to connect with the remote machine. I have access to everything on this machine. It doesn't seem this error is because of the remote machine. I think it relates to my simulation setup since it works for some other simulations for FSI problems!
    • Stephen Orlando
      Ansys Employee
      Thanks for the clarification.
      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. For CFX, 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.
      FSI simulations with very soft materials (like an elastic tube) or membranes are prone to numerical instabilities. In 2020R1 we have introduced a stabilization method in System Coupling called the Quasi-Newton Stabilization Algorithm. Note that this has to be used with the new System Coupling GUI or Command Line Interface that is run outside of Workbench. More information here: https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v221/en/sysc_ug/sysc_gen_scservice_dt_supplemental_iqnils.html
      The following tutorial, specifically this section: https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v221/en/sysc_tut/sysc_tut_oscplate_export_cfx_setup_export.html, shows how to set up a System Coupling case in Workbench and then export it to the new System Coupling GUI outside of Workbench. The new System Coupling GUI gives you access to more advanced features like Quasi-Newton Stabilization. This tutorial is for CFX and Mechanical, but the same export process, and System Coupling GUI setup process is valid for Fluent and Mechanical cases. https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v221/en/sysc_tut/sysc_tut_oscplate_export_cfx.html

      Steve
Viewing 5 reply threads
  • You must be logged in to reply to this topic.