[WIP] set Newton iteration maxIter to 50

[chongchonghe]

Description

We don't need a high value for maxIter since the Newton-Raphson iteration converges fast under the new base variables. We should also minimizing the average/maximal iterations for good performance.

Checklist

Before this pull request can be reviewed, all of these tasks should be completed. Denote completed tasks with an x inside the square brackets [ ] in the Markdown source below:

• I have added a description (see above).
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• I have added tests for any new physics that this PR adds to the code.
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[chongchonghe]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 2 pipeline(s).

[BenWibking]

This is somewhat dangerous, since this assertion does not actually work when running on GPU:

quokka/src/radiation_system.hpp

Line 1358 in 3085279

AMREX_ALWAYS_ASSERT_WITH_MESSAGE(n < maxIter, "Newton-Raphson iteration failed to converge!");

See #543.

[chongchonghe]

This is somewhat dangerous, since this assertion does not actually work when running on GPU:

quokka/src/radiation_system.hpp

Line 1358 in 3085279

AMREX_ALWAYS_ASSERT_WITH_MESSAGE(n < maxIter, "Newton-Raphson iteration failed to converge!");

See #543.

OK, I'll look into that when I get back to work next couple of weeks. I'll leave it here for now with a label "Do not merge".

[BenWibking]

This is somewhat dangerous, since this assertion does not actually work when running on GPU:

quokka/src/radiation_system.hpp

Line 1358 in 3085279

AMREX_ALWAYS_ASSERT_WITH_MESSAGE(n < maxIter, "Newton-Raphson iteration failed to converge!");

See #543.

OK, I'll look into that when I get back to work next couple of weeks. I'll leave it here for now with a label "Do not merge".

@chongchonghe Can you take a look at this again? I think this is the last thing before the radiation code can be used for production sims.

[chongchonghe]

Completed in #716