closure of equations

[Lilintal]

Hello,
I found this in a publication :
"the k - ε model has been chosen for the closure of time-averaged turbulent flow equations."
I have no idea of what does mean but maybe it is because of my bad physic memories...
Maybe is it something to do with what we call in French "limit" or "boundary" in a mathematical way ?
Thanks in advance for your help

 

[Donaldos]

Il s'agit vraisemblablement de mécanique des fluides, tu dois donc pouvoir utiliser le terme de fermeture, tout simplement.

 

[Salegrosso]

A possibility could be this one: The k-ε model has been chosen because, after passing to average with respect to time, the equations of a turbulent flow are closed.
The meaning of this 'being closed' could be that they correspond to a closed form.
In that case, as far as I know, under suitable regularity and topology assumptions (that is, differentiability and a simply connected domain), some vector quantity related to the fluid (as, for example, the fluid velocity), can be expressed as the gradient of a scalar function (the velocity potential, in the example).
In other words, closed forms in good domains admit scalar potentials.

I hope this fits with your context.

 

[Lilintal]

Thank you very much, both of you ! It did help =)

 

[Salegrosso]

You're welcome.