trixi-framework / trixi-framework/Trixi.jl

`VolumeIntegralSubcellLimiting` provides wrong `entropy_timederivative` values

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#2,948 0 comments 0 reactions 1 assignee Claimed by @bennibolm View on GitHub
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Description

`VolumeIntegralSubcellLimiting` provides wrong values for analysis quantities in `analysis_callback` that depend on the timederivative `du`.
This is because the `rhs!` call [here](https://github.com/trixi-framework/Trixi.jl/blob/ea79220f7dd05833e38f6c37a8c3576c752b6a67/src/callbacks_step/analysis.jl#L341) only computes the low-order update with `VolumeIntegralSubcellLimiting` and the high-order correction is later introduced by the stage callback `SubcellLimiterIDPCorrection`. However, the correction only modifies `u` but not `du`.

This leads to wrong values specifically in `entropy_timederivative` or `residual` quantities. We actually only analyze `entropy_timederivative` for the low-order contribution.

We should either find a way to fix this behavior or remove these quantities from the analysis callback.

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