Search found 37 matches

by Martin FERRAND
Thu May 30, 2019 3:56 pm
Forum: Code_Saturne usage
Topic: Boussinesq approximation
Replies: 6
Views: 1153

Re: Boussinesq approximation

Hello, since version 6.0 there is an option to activate the Boussinesq approximation (indeed rho varies only in the buoyancy term and is supposed to be constant everywhere else).
Look for idilat = 0 in cs_user_parameter file.

Best Regards
Martin
by Martin FERRAND
Thu May 30, 2019 1:42 pm
Forum: Code_Saturne usage
Topic: total pressure and gravity
Replies: 5
Views: 666

Re: total pressure and gravity

Hello, If you want to model a free surface, you can also test the ALE module and then “free surface” boundary condition will be used. It will impose p0 at the freesurface and let it move with the flow. So if you have breaking waves this method does not work. We have also experimental options for tha...
by Martin FERRAND
Thu May 30, 2019 1:38 pm
Forum: Code_Saturne usage
Topic: VOF and ALE compatible?
Replies: 3
Views: 474

Re: VOF and ALE compatible?

Hello, It should be compatible but we don’t have any validation test case for that so that would be nice if you could set up a toy model test case to check if it is working correctly. If not, that will not be a big deal to fix (ALE is mainly impacting the other fields updating convective mass flux, ...
by Martin FERRAND
Fri Sep 07, 2018 9:03 am
Forum: Code_Saturne usage
Topic: Initializing turbulent flow
Replies: 4
Views: 1133

Re: Initializing turbulent flow

Hello, Concerning the initialisation you can read paragraph 6.3 of the user guide of version 5.0 for instance. Concerning the inlet BC for turbulence, you can either chose established profile with an hydraulic diameter given by the user, or hydraulic diameter and a turbulence intensity. See for inst...
by Martin FERRAND
Fri Sep 07, 2018 7:11 am
Forum: Code_Saturne usage
Topic: Usage of ALE Module in a duct
Replies: 3
Views: 579

Re: Usage of ALE Module in a duct

Hello, Is it a valve you want to model? If yes, this boundary should be considered as moving walls. If it is inlet outlet boundary conditions, as mention in the user and the theory guide, isolib BC type retain the flow (imposing a 0 mass flux) when entering (it is a free outlet, but not inlet is all...
by Martin FERRAND
Wed Nov 08, 2017 9:10 am
Forum: Code_Saturne usage
Topic: cs_user_head_losses.c vs cs_user_source_terms.f90
Replies: 1
Views: 494

Re: cs_user_head_losses.c vs cs_user_source_terms.f90

Hello Daniele,
That is not normal. What is the version you are using?
Best regards
Martin
by Martin FERRAND
Mon Oct 09, 2017 8:47 am
Forum: Code_Saturne usage
Topic: Zero gradient at certain faces
Replies: 26
Views: 6377

Re: Zero gradient at certain faces

Dear Odion,

a call function was missing for the vector coupling. I added that to the trunk version. The computation is not crashing anymore but the solvers are not converging properly.

I look at it in the coming days.

Best Regards

Martin
by Martin FERRAND
Mon Sep 25, 2017 7:57 am
Forum: Code_Saturne usage
Topic: Constant Diffusivity of scalar with drift flux in CS 5.0.4?
Replies: 5
Views: 1092

Re: Constant Diffusivity of scalar with drift flux in CS 5.0

Hello,
You can activate a variable diffusivity and give the same value for all the cells. We have to correct this combination.

Best regards

Martin
by Martin FERRAND
Tue Sep 27, 2016 6:11 am
Forum: Discussion
Topic: How to integrate a new term in equation for scalar ?
Replies: 9
Views: 4809

Re: How to integrate a new term in equation for scalar ?

Hello again,
Just a small additional remark: is "ni" a component of a vector? If so, I would suggest you to move to the trunk version because we add the capability to transport vector species (or if not it will be in the coming days).
Best regards
Martin
by Martin FERRAND
Mon Sep 26, 2016 8:11 pm
Forum: Discussion
Topic: How to integrate a new term in equation for scalar ?
Replies: 9
Views: 4809

Re: How to integrate a new term in equation for scalar ?

Hello Paul, Reading your problem, I think you can do it using DRIFT modelling. Your scalar is nothing else that transported by the velocity u plus a drift (proportional to grad phi). This is possible in version 4.0 to activate drift to a scalar (look at DRIFT in cs_user_parameters.f90) but usually t...