Learning Forum

[Jiayue]

I did the case of two-way FSI by the Ansys workbench 2020 R2 version, involving Fluent and Transient structural modules.Using the SST K-W transient turbulence model and the dynamic grid in the FLUENT; The rotation and translation of members are defined in the structural field. After all settings are done, update the system coupling, and the following error message will appear:

Error：Update failed for the Solution component in System Coupling. The coupled update for system Fluid Flow (Fluent) threw an exception. Update Solution Failed

Error：(DP 0) A solver failure occurred during the run in the Fluid Flow (Fluent) system

Error：(DP 0) An unknown error occurred during solution. Check the Solver Output on the Solution Information object for possible causes.

Error：(DP 0) An unknown error occurred during solution. Check the Solver Output on the Solution Information object for possible causes.

Error：(DP 0) An unknown error occurred during solution. Check the Solver Output on the Solution Information object for possible causes.

Warning：(DP 0) One or more MPC contact regions or remote boundary conditions may have conflicts with other applied boundary conditions or other contact or symmetry regions. This may reduce solution accuracy. Tip: You may graphically display FE Connections from the Solution Information Object for non-cyclic analysis. Refer to Troubleshooting in the Help System for more details.

Error：(DP 0) Participant Solution 1 encountered a fatal error. Message: The slave term of internal constraint equation 1 could not be identified. Please do not save the project if you would like to recover to the last saved state.

Error:(DP 0) Participant Solution 1 encountered a fatal error. Message: The slave term of internal constraint equation 1 could not be identified. Please do not save the project if you would like to recover to the last saved state.

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Tested individually, the grid is no problem! Modified many times, still can't solve the problem, please help

[Stephen Orlando]

It looks like these are errors from Mechanical. Please review the Mechanical setup.
I recommend going over this tutorial in the Ansys documentation that shows a 2-way FSI simulation with Fluent and Mechanical. https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v221/en/sysc_tut/sysc_tut_reedvalve_fluent.html
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/v221/en/sysc_ug/sysc_bestpractices_fsi.html