How to define a region with a fixed refinement level?

[Pockjob]

Hi everyone,
Is it possibile to define a region with a fixed refinement level lower than the maximum level? For example, I want to fix the refinement level in the sepecified region as 1 but the maximum refinement level is 2 in other region. How can I get it?
Thanks.

[baperry2]

You can set a region for refinement to a specific level less than the overall maximum level using the following:

amr.max_level = 2

...

tagging.refinement_indicators = yLow
tagging.yLow.max_level = 1
tagging.yLow.in_box_lo = -0.1  -0.52  -0.85
tagging.yLow.in_box_hi =  3.1 -0.45    0.85

This will tag the specified region for one level of refinement, while allowing you to have other refinement indicators to higher levels. However, note that if your other refinement indicators are active in the specified region, then this region could still end up with more than one level of refinement. There isn't a built in way to set an overall maximum level in one region only that would prevent other refinement indicators from adding refinement, except for the special case of refining an EB surface.

Another option would be to code up any custom refinement logic that you want using the problem-specific tagging functionality (See the TG RegTest).

More discussion of tagging criteria is available here: https://amrex-combustion.github.io/PeleC/InputFiles.html#tagging-criteria

[Pockjob]

Thank you very much. I will try it.