blastAMR stuck in inifite loop

[JanGaertner]

blastAMR gets stuck in an infinite loop in Foam::refinement::consistentRefinement() because nChanged never becomes zero. The edgeConsistentRefinement() always returns 1 for the same cell in an infinite loop.

In the case of the tested mesh it was due to cellJLevel > (cellILevel +1)

Note: this was tested with labelsize=64. However tested that the conversion to int for the const cellJLevel worked correctly.

Not sure what edgeConsistentRefinement() does and how to fix this issue.
Also an interesting fact is that the problem can be avoided for some time if shortly before the time step is written. Then it runs a bit longer before it gets stuck again.

[FoamScience]

This is probably case-specific as some combinations of mesh settings and decomposition parameters may cause this. Experiment with the number of buffer layers between refinement levels nBufferLayers.

If all else fails, increase your initial mesh density and set maximum refinement level to 2 (so the edge consistency check is not performed).

I'd be interested in seeing the specific mesh which led to this behavior though. Might be a good idea to add it to unit tests

[JanGaertner]

I cannot upload the blockMesh dict here. Should I send it to you by e-mail?

[rpasolari]

Hello! I am recently facing this same infinite loop issue with consistentRefinement().

Did you ever find a specific solution or a workaround for this?

[FoamScience]

As a general rule, the polyRefiner is prone to these kind of "bugs". So try the hexRefiner if you encounter this often with your meshes - at least for now.

In principle, the AMR should succeed regardless of maxRefinement but decreasing that may also help (start with a denser mesh but use less refinement levels).

Currently, I don't have the capacity to look into this in detail - but if an easy to run case is provided that suffers from this, I can take a quick look (eg. any OpenFOAM tutorials... etc).