Convert files to the new pyfr format

General
1

Hi,

I wonder if you have some scripts to convert mesh and solution files from old pyfr versions (<2.1) to the newer versions?

Regards,

Zhenyang

2

The new mesh format is node based and so it is difficult to reconstruct from the old format. As such a converter is not available. With that said, if one has the underlying .msh file it is possible to just reimport. The solution files are a bit simpler and so in principal it is possible to put together a script with a few dozen lines which moves things over (assuming the mesh has been recreated).

Regards, Freddie.

4

Thanks, I manage to have a converter. An follow up on the latest solver version: is the entropy filter still suitable for the anti-aliasing purposes? As in this paper: [2302.13359] On the anti-aliasing properties of entropy filtering for discontinuous spectral element approximations of under-resolved turbulent flows

5

Yes, it can absolutely be used. Note that we have found it to cause issues for acoustic problems but if you’re not interested in acoustics then it does appear to work extremely well and at a much lower cost than anti-aliasing.

Regards, Freddie.

6

Can you be more specific on the known acoustic problem? I am working on acoustics problems.

Regards,

Zhenyang

7

When we have used it on a rod-aerofoil problem (paper on the physics has been accepted, should be published soon) we found that entropy filtering got us the CFD metrics correct but the FWH results were wrong. As such we had to switch to using anti-aliasing. This was with a slightly older formulation of entropy filtering compared with what is currently in PyFR, however, so it is possible that recent changes will do better.

Regards, Freddie.