open TELEMAC-MASCARET The mathematically superior suite of solvers

bonjour,

j'ai deux questions concernant les conditions aux limite du modèle k-epsilon sur les frontières liquides pour TELEMAC 3D , et je me réfère au livre du monsieur Hervouet (hydrodynamique des écoulements a surface libre)

" sans information supplémentaire sur la valeur K et epsilon ...on impose ϑt(∂ε/∂n)=0 ϑt(∂k/∂n)=0 ."

De quelle information s'agit-il ?

Peut-on accéder au code source pour changer ses conditions ?

merci pour votre aide

Hello,

There are several things:

On lateral boundaries you have now a keyword :

OPTION POUR LES CONDITIONS AUX LIMITES DU K-EPSILON
OPTION FOR THE BOUNDARY CONDITIONS OF K-EPSILON

with 1 : no turbulence
2 : Hans and Burchard formula (based on a logarithmic profile)

For the bottom and free surface, you can change in subroutine cstkep.f the values of LIMKF, LIMEF, LIMKS, LIMES to get Dirichlet or Neumann conditions for k and epsilon on the free surface and the bottom. When it is Dirichlet the formulas are in subroutine kepcl3.f and can be changed. For example LIMKF is for K on the bottom (Fond).

The default, as said in the book, is Neumann because all other formulas for Dirichlet values assume a logarithmic profile, and we do not know in advance your case, e.g. if you have wind the formulas will be wrong, and the same for any situation where there is no logarithmic profile.

I hope this clarifies the matter,

With best regards,

Jean-Michel Hervouet

je vous remercie , je vais essayer cette approche