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jaheyns / CfdOF

Computational Fluid Dynamics (CFD) for FreeCAD based on OpenFOAM solver
GNU Lesser General Public License v3.0
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Cfdof/FreeCAD 0.21.2 Generates Incorrect Periodic B.C.'s #161

Closed hooshsim closed 1 month ago

hooshsim commented 1 month ago

Huge thank you to the development team for implementing periodic boundary conditions in the latest version of FreeCAD/CfdOF...a job well done!

To take advantage of the periodic boundary conditions, I built a sector model of an axial fan installed in a wind-tunnel. In my model, I assigned P1 as slave and P2 as master surfaces using rotational option. Then I updated the fan patch in the boundary field file (0/U) for rotationality. I ran the case for about 300 iterations without any issues. The predicted moments were much smaller than expected ones. After checking the 0/U file, I realized that slave surface (P1) is missing from the patch list in the boundary field file as shown below.

I also changed p2_slave to P1_slave and re-ran the case and no improvements in the solution. Any suggestions or recommendations?

P2_master { type cyclicAMI; }

P2_slave { type cyclicAMI; }

Thank you

hooshsim commented 1 month ago

Couldn't upload the case file due to unsupported file type.

oliveroxtoby commented 1 month ago

Couldn't upload the case file due to unsupported file type.

Could you try zipping it or uploading it on the forum please?

hooshsim commented 1 month ago

Thanks Oliver. See the attached zip file.

Fan1.zip

oliveroxtoby commented 1 month ago

This is actually the expected behaviour. The master and slave patches are renamed as (master patch name)_master and (master patch name)_slave for internal reasons - so the P1 patch is not missing, it is just renamed to P2_slave. It's just a matter of naming so should have no bearing on results.