A question on the large eddy simulation model.

[esaka-forever]

Dear xcompact3d community,
First of all, I am using the 4.0 version (I guess this may be one cause of my issue). I realize when specifying the LES model. some example folders have used "jles = " while some parameter file in the channel folder is using "iles = ". So which one is actually functioning? It looks like parameter "iles" is not actively used in the program?
Meanwhile, when I use “jles” to simulate a implicit LES (by setting jles=4), the results is exactly the same as when I set jles=0. I remember some xcompact3d paper says the implicit LES has adopted a more dissipative scheme. So how to activate that dissipative scheme? Any help is appreciated !!!

[slaizet]

Hi,
iles has now been removed in the latest versions of the code. To activate the LES mode, you need to have ilesmod=1 and then you can select which jles you want.
Best,
Sylvain

[esaka-forever]

Thank you for the reply. Another issue is that, when I want to use implicit les, I set jles=4, but the results are exactly the same as when I set ilesmod=0. Is that normal? I think the Xcompact3d paper said the implicit les has adopted a more dissipative scheme somewhere.

[slaizet]

As per my previous message, you need ilesmod=1 to activate the LES mode.
Best,
Sylvain

[esaka-forever]

Thank you.

[brunoscapin1]

esaka, if you want to use the iles method make sure you also set isecondder = 5, so that the code calculates the scheme's coeff considering the isvv constrains (see schemes.f90 l.467 for more info).

[esaka-forever]

I see. Thank you for the help !