Dear All, How to evaluate this article? " On the physical inadmissibility of ILES for simulations of Euler equation turbulence" [[1811.05888] On the physical inadmissibility of ILES for simulations of Euler equation turbulence]
Is the view in this article about ILES correct?
I’m not exactly sure which part you are asking about. ILES doesn’t use an explicit sub-grid model and instead uses the dissipation of the numerical scheme at high frequencies to give an implicit SGS model.
I haven’t read the whole paper, but on there conclusion about the discrete entropy inequality, I don’t fully agree with what they say. I don’t think it’s ILES per se that leads a scheme to not obey the discrete entropy principle, but rather the numerical scheme itself. By adding a model this will add dissipation to the scheme which in term will push the scheme closer to obeying the discrete entropy inequality. But without setting the model dissipation with that inequality in mind, I don’t how it can always obey it.
My view is you are probably best of starting with an entropy stable numerical method and then adding a SGS model to it. That way you can separate the issues of accurately modelling sub-grid scales and entropy stability. In reality the there is some coupling between the issues, but it is just easier to treat them separately.
Thank you very much ! My intuition makes me prefer your statement, but I still hope to get a more powerful response to this article through theoretical analysis,