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[SickOfAnsys]

Recently learned how to mesh using ICEM (to a fashion), and export this mesh to FLUENT to solve. Now whenever I use these meshes in my simulation I get the error "floating point exception". This never used to happen when using the standard meshing software in workbench, so I'm guessing it's an issue with the mesh coming from ICEM.

I run diagnostics of the mesh prior to exporting it to FLUENT and there are no errors. I assign boundaries prior to exporting the mesh and assign the boundary types also.

[Keyur Kanade]

18.2 is very old version. Please try latest 2022R1 version.
Meanwhile you can check if you can import that mesh file in Fluent Meshing. Then you can check mesh in Fluent Meshing as well.
Regards Keyur
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[SickOfAnsys]

Can you send me a copy of 2022R1 with the accompanying research license then, please.

[Rob]

The current release can be downloaded from the Customer Portal, and the University should have an up to date licence.
However, given the shape I'd run this through Workbench Meshing and use sweep with an unstructured face mesh. What does Fluent report on a mesh check? What models are you using in Fluent?

[SickOfAnsys]

I contacted the university licensing manager earlier but unfortunately they're on strike at the moment I'll be waiting until they can clear the backlog before they get to my email.
When I ran Fluent report it stated that there were left-handed faces so I re-did the mesh and corrected that error. Not sure how to check for this with ICEM.
I also noticed also that when exporting the mesh from ICEM it exported it as a solid to begin with, and after I attempted to set the faces and the walls manually it exported the geometry as a mixture and came up with the error that the boundary zone was adjacent to a solid zone. Not sure how I did that, nor how to repair it so I deleted it. I re-meshed the geometry and managed to export it as a fluid and got it working fine. Not the most efficient way of working and it did not make for the most fun weekend!
The current geometry example is a simple geometry that is a component part of a larger serpentine geometry. I found the serpentine geometry more difficult to mesh using Workbench Meshing so I tried ICEM (huge learning curve). ICEM does seem to give the user more control over the meshing process when compared to the Workbench Meshing but it is tricky to catch errors before exporting to FLUENT.
The models that I am using are the Energy equation and viscous laminar flow and I use UDF's for the inlet velocity profile and also for the outlet temperature profile.

[Rob]

OK, we can't do much about your IT department!
In Fluent you can change cell zone types so if ICEM CFD has set something to solid just change it. That should resolve errors relating to inlets/outlets next to solid zones. You may also need to check the wall + wall:shadow pairs to make sure the channel is open.
ICEM CFD has a huge learning curve, and is no longer widely used. I used it's predecessor at Uni in the mid-late '90s and then didn't learn the new version following the Ansys acquisition of Fluent. The TUI tools,
//mesh/repair-improve>
may help.

[SickOfAnsys]

Cheers Rob, I'll look into modifying the cell zone types when my current simulation finishes!
It's not the whole IT department, just the senior members; junior members of staff have been unofficially threatened not to take industrial action as it may negatively impact on potential future progression up the career ladder (politics).
Is ICEM still available with the newer versions of Ansys? I've been using it constantly for days now and growing as close to fond of it as I healthily can.
The TUI tools did not rectify the left-handed faces, but did not try it for the boundary errors.

[Rob]

ICEM CFD is still available, but I'd focus more on Fluent Meshing, and more specifically the watertight workflow for most applications. Given you're looking at a swept mesh you're not using the wrong tool, but you will find the newer options to be easier to use, and better as features continue to be added.