problem with LES

[chengan.wang]

Hello everyone

Now I'am working on the natural convection (Boussinesq approximation) with a high Ra number 1.5x10⁹ in a square geometry(1mx1m).The mesh is 100x100. With this mesh for a small Ra=5x10⁶ and laminar flow, the result is good. When I increase the Ra number with 1.5x10⁹, the flow is turbulent, so I use the LES model(Smagorinsky), some errors happens as shown in the file attachement. I think it is not the problem of the mesh because I've tried with a mesh 150x150. If I forget to add subroutine when I use the model LES? Besides,Smagorinsky model propose the subgrid viscosity for the Navier-stokes, if I need to add the model of subgrid thermal diffusivity for energy equation?

Thank you very much

Chengan

[Yvan Fournier]

Hello,

You seem to have forgotten the attachment.

Regards,

Yvan

[chengan.wang]

Sorry, I've added the attachment 'listing.txt', Thanks

[Yvan Fournier]

Hello,

Are you using the usini1.f90 user subroutine, the GUI, or both ? Did you check for the options mentioned in the error message ? Could you post that data ?

Regards,

Yvan

[chengan.wang]

Hello,

In fact, I couldn't find the options in "cavite.xml" they mentioned in the listing

@ La version actuelle ne le permet pas lorsque l'une des
@ options suivantes a ete activee (c'est le cas ici) :
@ - utilisation d'un estimateur d'erreur (IESCAL)
@ - couplage instationnaire (IPUCOU)
@ - prise en compte specifique de la pression
@ hydrostatique (IPHYDR et ICALHY)
@ - pas de temps variable en temps ou en espace ou
@ algorithme stationnaire (IDTVAR)

By the way, If you have some exemple which use LES model?

Thanks.

Chengan

[Jacques Fontaine]

Hello,

Are you using usini1.f90?
Could you attach your user Fortran files?

Best regards,
JF

[Yvan Fournier]

Hello,

IPHYDR is the keyword for the "improved" option of "pressure interpolation in stratified flow", so you must use the "standard" option.

Best regards,

Yvan

[chengan.wang]

Hello

I didn't add usini1.f90 in folder "SRC".

Best regards.

chengan

[chengan.wang]

Hello,

finally when I change the scheme as "centered"(before I use upwind for the Velocity). The software can work now. It is strange that we don't need the upwinding for the velocity.
Here I have another question:
When I select the LES model, the momentum equation is automatically changes with turbulent viscosity. But for the scalar equation, like temperature, if I need add some turbulent model (like considering the turbulent thermal diffusivity) to the source term?

Best regards

Chengan