Search found 44 matches

by Martin FERRAND
Wed Dec 16, 2015 8:36 am
Forum: code_saturne usage
Topic: start calculation -> nothing happens
Replies: 9
Views: 4594

Re: start calculation -> nothing happens

Hello,
When using a tetra mesh, we advice to activate "least square with extended neighbourhood" gradient calculation method in the GUI (or set: imrgra=2 in cs_user_parameters.f90).
Best regards
Martin
by Martin FERRAND
Tue Dec 15, 2015 1:46 pm
Forum: code_saturne usage
Topic: start calculation -> nothing happens
Replies: 9
Views: 4594

Re: start calculation -> nothing happens

Hello,
In paraView, to visualise the fluid volume only (and not the boundary mesh) you should use filter->alphabetical->extract block
Then you can select the fluid domain only et click on apply.
You will be allowed to visualise pressure, velocity, etc
Best regards
Martin
by Martin FERRAND
Wed Dec 09, 2015 7:28 pm
Forum: code_saturne usage
Topic: The problem about 2D turbulent flat plate
Replies: 12
Views: 7373

Re: The problem about 2D turbulent flat plate

Hello, concerning questions 1-5 of the message: Hello, Yvan I am sorry to disturb you again. In the last three months, I prepared the exam, and delayed my work. Recently I continue to simulate 2D turbulent flat plate(use SST model). As your suggestion, I generate a new mesh, and have any waring abou...
by Martin FERRAND
Wed Dec 09, 2015 7:07 pm
Forum: code_saturne usage
Topic: The problem about 2D turbulent flat plate
Replies: 12
Views: 7373

Re: The problem about 2D turbulent flat plate

Hello, concerning your "problem" mentioned in: Thank Yvan for your reply! I'm a postgraduate from Northwestern Polytechnical University, China. Our research direction is lattice Boltzmann method(LBM). Since last September, I interested in Finite Volume LBM(FVLBM), and finial choose Code_sa...
by Martin FERRAND
Thu Nov 19, 2015 8:51 pm
Forum: code_saturne usage
Topic: Tensor scalar diffusivity
Replies: 3
Views: 3154

Re: Tensor scalar diffusivity

Hi Jacopo,
we could provide to the user the possibility of doing so in case of Eddy Viscosity Model. Yes, to distinguish the scalars, it is possible to play around with a Prandtl or a Schmidt turbulent number (it is ctheta for tensorial diffusivity).
Cheers
by Martin FERRAND
Thu Nov 19, 2015 5:08 pm
Forum: code_saturne usage
Topic: Tensor scalar diffusivity
Replies: 3
Views: 3154

Re: Tensor scalar diffusivity

Hello, There exists an option to activate tensorial diffusivity for a scalar without choosing RSM Models. Set "idften(ivar)=6" in usipsu, and then compute the field "visten" (look in covofi to access to it) in cs_user_physical_properties". Warning, you can't specify differen...
by Martin FERRAND
Thu Nov 19, 2015 7:46 am
Forum: code_saturne usage
Topic: 0-equation turbulence model
Replies: 3
Views: 2389

Re: 0-equation turbulence model

Hello,

Your proposition is the best. Do not forget to activate a variable molecular viscosity.

Best Regards
Martin
by Martin FERRAND
Thu Nov 05, 2015 7:39 pm
Forum: code_saturne usage
Topic: Boundary condition at inlet
Replies: 7
Views: 3943

Re: Boundary condition at inlet

Hello, As a convention, we take negative mass flux for inlets (because as a convention, the normal to the boundary is outwarding) so no matter of the direction of z. Concerning your crash, what I advice is to extrude your mesh next to the outlet (because the pressure BC is supposing that the mesh is...
by Martin FERRAND
Thu Nov 05, 2015 5:13 pm
Forum: code_saturne usage
Topic: subroutine not over-riding GUI boundary conditions - ALE
Replies: 13
Views: 7839

Re: subroutine not over-riding GUI boundary conditions - ALE

Hello, You can specify the initial water elevation by modifying this vectorial field in cs_user_initialisation.f90. Then, by default, a imposed pressure is imposed at the free surface (with p0 value) and a homogeneous Neumann on the velocity. Concerning the mesh velocity, the normal component to the...
by Martin FERRAND
Tue Nov 03, 2015 9:03 am
Forum: code_saturne usage
Topic: subroutine not over-riding GUI boundary conditions - ALE
Replies: 13
Views: 7839

Re: subroutine not over-riding GUI boundary conditions - ALE

Hello, If you want to specified an initial mesh_displacement (for an initial water elevation), you can do it in cs_user_initialization. The boundary condition imposed in case of free surface is an imposed pressure (at p0) and an homogeneous Neumann on the fluid velocity (so no additional shear stres...