2D turbulent channel flow: pb with TKE results

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gina

Re: 2D turbulent channel flow: pb with TKE results

Post by gina »

thanks Mickaël,
I will do the simulation with you.xml file, and i will tell you about the result.
gina

Re: 2D turbulent channel flow: pb with TKE results

Post by gina »

please why you take ref velocity=79.2m/s?
gina

Re: 2D turbulent channel flow: pb with TKE results

Post by gina »

Hello Mickaël,
I do my simulation with your .xml file, then I compare k+=f(y+)  for saturne simulation and DNS, BUT this time the TKE is very high! you can see that in the attached doc.   
Attachments
saturne2_DNS.doc
(144 KiB) Downloaded 147 times
Mickael Hassanaly

Re: 2D turbulent channel flow: pb with TKE results

Post by Mickael Hassanaly »

Gina,
The velocity i set up allows to have turbulent Reynolds = 590. And if compute k+=f(y+), my maximum value of k+ is about 3.5 because my max k is 8.78 J and turbulent friction velocity uk = 1.60m/s. Do you agree with me?
Mickaël
gina

Re: 2D turbulent channel flow: pb with TKE results

Post by gina »

Hi Mickaël,
with the .xml file that you  send me, I found the maximum k=38.609639!!!
Mickael Hassanaly

Re: 2D turbulent channel flow: pb with TKE results

Post by Mickael Hassanaly »

Is k turbulent kinetic energy in your case? If yes, check your listing file at the last time step, you should have the value of turbulent kinetic energy printed. What's the value you read, please? And for my own curiosity, how do you get k=38.609639? Maybe we are not talking about the same thing so i need it to be clear to help you.:-)
gina

Re: 2D turbulent channel flow: pb with TKE results

Post by gina »

Thanks Mickaël,
yes i have take turbulent kinetic energy in my case, and to obtaind it,  in GUI saturne profile I choose the position of x1=100 to x2=100
                 y1=0 to y2=1
                 z1=0 to z2=0
and i take turbulent energy
 
when the simulation is finish, i obtened the data of k=f(y) 
then, i calcultate k+=k/(u_tau*u_tau)
                           y+=y*u_tau/viscosity
gina

Re: 2D turbulent channel flow: pb with TKE results

Post by gina »

you can find as attached, the xml file which i have run, you can run it as it is to check my results.
and you find also the TKE file which i obtained in  (tmp_Saturne) folder.
to calculate k+ and y+, I take u_tau=1,00005 m/s and viscosity=0.001695
how do you have k=8.78? where you obtains it?
have you plot k+=f(y+)?
thank you to light me
Attachments
TKE.dat
(3.7 KiB) Downloaded 151 times
helf_channel_M.xml
(7.15 KiB) Downloaded 152 times
Mickael Hassanaly

Re: 2D turbulent channel flow: pb with TKE results

Post by Mickael Hassanaly »

Gina,
could you send me your listing file, please?
Mickaël
Mickael Hassanaly

Re: 2D turbulent channel flow: pb with TKE results

Post by Mickael Hassanaly »

Are you sure to use my xml file?
By the way, could you run Code_Saturne in debug mode, please?
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