[sita]

Hi all,


Recently I learnt about the existence of the patchGroups utility in OpenFOAM, which seems really useful. I'm struggling with the implementation though. Firstly, I seem to be unable to find anything about patchGroups in the documentation of OpenFOAM-5.x (I'm currently using OpenFOAM-5.x on a Scientific Linux cluster), but I noticed that e.g. the motorBike tutorial still uses patchGroups, so apparently the utility still exists.

My question pertains to a mesh that I imported from Numeca's Hexpress. Hexpress provides the option to export a mesh to OpenFOAM format, which seems to work fairly well, as far as I can tell now. My mesh contains a large body, which is divided into sub-parts. According to constant/polymesh/boundary, all these patches are of the type wall, just like they're supposed to be. However, when I view the mesh in ParaView, those patches turn up as type patch, which may be (part of) the cause of my problem.

The online documentation for OpenFOAM 2.2.0 says "All constraint boundary types, e.g. empty, processor, etc. are automatically placed into a patch group of the same name."

So I would expect all patches of type wall to be grouped into a group called 'wall' or something, but this doesn't seem to be the case.

Is this behaviour (automatically placing patches of the same constraint boundary type into one group) still present in OpenFOAM-5.x?

If not, or if something about my imported mesh somehow disables this behaviour, is there a way to create such groups? I read about using regular expressions for patch naming, but I'm not sure how to apply that to an imported mesh. Could I use regular expressions in my initial condition files for example?

Many thanks!
Sita

[sita]

Sorry, in the meantime I've figured out that it's indeed possible to use regular expressions in the initial conditions files, so that question is answered now - I can manually group all my wall patches.


Still, it would be really convenient if OpenFOAM did this automatically, so my other question remains open.

[tomf]

Hi Sita,

Usually when importing a mesh from a third party application we first run renumberMesh. This typically also makes these patchGroups. I think these patchGroups are in all latest versions of the foundation and ESI forks.

Regards,
Tom

[sita]

Hi Tom,

Ah perfect, I'll give that a try, thanks!

Sita