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ExtremeFLOW / neko

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https://neko.cfd/
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Add Sigma and Smagorinsky model, fix the Vreman model. #1265

Closed timofeymukha closed 1 month ago

timofeymukha commented 2 months ago

This PR pulls in the Sigma and Smagorinsky models implemented on the stress formulation branch, developed by @Shiyu-Sandy-Du and @muenschm . Also fixes a bug in the Vreman model (a **2 was missing).

Shiyu-Sandy-Du commented 1 month ago

What does the standard specify here? To my probably outdated knowledge: acos -> REAL(4) and dacos -> REAL(8). In case this is still true, we should not change this.

acos(X) returns the same data type as X. See https://gcc.gnu.org/onlinedocs/gfortran/ACOS.html. And the "real precision" is specified according to the system :) (could be either double or single)

timofeymukha commented 1 month ago

Thanks for fixing the precision issues. Someone else but us 3 should look at the PR before we merge, though since you two are the authors :-). I will make a request.

timfelle commented 1 month ago

Well I dont know much about the method but it seem valid enough as is.

Two things though,

Shiyu-Sandy-Du commented 1 month ago

Well I dont know much about the method but it seem valid enough as is.

Two things though,

  • Do you have an example that can be submitted along with the PR.
  • Could you please update the documentation with some words on this method and how it can be used?

For the first question: It could be tested with any example as long as it solves the Navier-Stokes. Now the tested one is tgv. Should we update the json file for tgv example? (I don't think we should change anything in the examples at this stage because the sgs model needs stress formulation to test, which is not included in this branch and we performed tests on that branch. As a result, sgs stress will not be coupled in this branch.)

timofeymukha commented 1 month ago

Yes, an example will have to wait until we actually have stress formulation. With the documentation, it is a bit the same -- since we cannot actually use the models right now, we cannot add instructions. But I pinky-promise that we will add it later :-).