Search found 280 matches

by Luciano Garelli
Wed Nov 16, 2016 7:04 pm
Forum: code_saturne usage
Topic: Backflow problem in LES
Replies: 9
Views: 9379

Re: Backflow problem in LES

Muhsin, In sections 5.2 and 5.4.4 of the theory guide of CS ( http://code-saturne.org/cms/sites/default/files/docs/4.0/theory.pdf ) you can find a more detailed answer to this question. Outlet BC " Warning: if the outgoing mass-flux is negative, i.e. if the outlet becomes an inlet, then the mas...
by Luciano Garelli
Wed Nov 16, 2016 5:41 pm
Forum: code_saturne usage
Topic: Backflow problem in LES
Replies: 9
Views: 9379

Re: Backflow problem in LES

Hello Mushin, I don't understand your question..but in your listing file you have a negative mass flow at inlet and a positive mass flow at outlet. The sign of the mass flow at boundaries depends on the sign of \vec{V} \cdot \vec{n} . When you activate the gravity, Are you also impousing a velocity ...
by Luciano Garelli
Wed Nov 16, 2016 4:09 pm
Forum: code_saturne usage
Topic: Backflow problem in LES
Replies: 9
Views: 9379

Re: Backflow problem in LES

Hello Mushin, I was looking at your listing file. At start of your simulation you have an important density difference (481.81 MIN, 589.92 MAX) so, this could lead an important bouyancy (body) force. Did you try to reduce the value of the imposed gravity in order to reduce this forces? Because, as y...
by Luciano Garelli
Mon Nov 14, 2016 4:25 pm
Forum: code_saturne usage
Topic: Backflow problem in LES
Replies: 9
Views: 9379

Re: Backflow problem in LES

Hello Mushin,

Could you solve your problem? If not, could you upload a small problem where the case fails.

Regards,

Luciano
by Luciano Garelli
Mon Nov 14, 2016 4:11 pm
Forum: code_saturne usage
Topic: Internal wall not detected in code saturne 4.2
Replies: 14
Views: 11975

Re: Internal wall not detected in code saturne 4.2

Hello Sagar, I uploaded an user function and a case file where your problem it is working (I attach a figure). I used the default values in the user fuction like in the /REFERENCE/cs_user_mesh.c using as selection criteria "8" and the same selection criteria in the GUI to impose the wall B...
by Luciano Garelli
Wed Nov 09, 2016 10:59 pm
Forum: code_saturne usage
Topic: Heated square cavity flow Tutorial 3 in Code Saturne 4.0
Replies: 11
Views: 10960

Re: Heated square cavity flow Tutorial 3 in Code Saturne 4.0

Hello,

I didn't find anything strange in the listing. I attach a case file and a mesh which I get the solutions like in the tutorial.

Try to compare this case file with your case file in order to find the difference,
Results_vel.jpg
Results_temp.jpg
Regards,

Luciano
by Luciano Garelli
Wed Nov 09, 2016 4:45 am
Forum: code_saturne usage
Topic: Heated square cavity flow Tutorial 3 in Code Saturne 4.0
Replies: 11
Views: 10960

Re: Heated square cavity flow Tutorial 3 in Code Saturne 4.0

Hello,

Are you following the tutorial? The expected results are shown at the end of the pdf.

Could you post the listing file.

Regards,

Luciano
by Luciano Garelli
Mon Nov 07, 2016 3:06 pm
Forum: code_saturne usage
Topic: free surface not moving
Replies: 21
Views: 15418

Re: free surface not moving

Hello Olivier, I was debuging the alelav.f90 subroutine and I found that may be there is a bug in the following line, because to get the type of boundary condition at the boundary face ifac is used itypfb(ifac). if (ialtyb(ifac) .eq. ifresf) then so if you change to if (itypfb(ifac).eq.ifresf) then ...
by Luciano Garelli
Thu Nov 03, 2016 5:55 pm
Forum: code_saturne usage
Topic: Heated square cavity flow Tutorial 3 in Code Saturne 4.0
Replies: 11
Views: 10960

Re: Heated square cavity flow Tutorial 3 in Code Saturne 4.0

Hello,

CFL -> Courant–Friedrichs–Lewy (CFL) condition.

https://en.wikipedia.org/wiki/Courant%E ... _condition

Regards,

Luciano
by Luciano Garelli
Thu Nov 03, 2016 4:01 pm
Forum: code_saturne usage
Topic: Heated square cavity flow Tutorial 3 in Code Saturne 4.0
Replies: 11
Views: 10960

Re: Heated square cavity flow Tutorial 3 in Code Saturne 4.0

Hello, You need a temperature reference state for the Boussinesq approximation. The tutorial mention that "The reference state is taken at the cold wall temperature", so the Tref sould be 293.15K. For convergence checking as mentioned in the tutorial you can " Verify that the residual...