turbine modelling

[JamesMcNaughton]

Regarding the meshing you only need to mesh the fluid which I don't think you have. I'll draw a picture it might be easier.,.

[JamesMcNaughton]

Hey, so in 2D this is the meshing strategy you should have. You don't need to mesh the solid outer blades just the fluid around them. Likewise for the inner turbine. So two meshes separated by the cylindrical interface (it doesn't need to be cylindrical but if you want to rotate the mesh it will).

Apologies if this is what you have just I cannot see it from your pictures and wanted to be sure you're on the right track..

[stage75]

Hello James,

That's ready what you drew, I attached a picture of my geometry.
But I don't understand how I can declare my turbine as a solid in a coupling SATURNE/SATURNE (saturne that modeling the fluid, no?)

[JamesMcNaughton]

As you say saturne only models the fluid and only needs to know there is a wall. You just define the turbine boundary as a wall (iparoi) in usclim.

Have a look at some of the examples to see what I mean but you only need to mesh the fluid.

cheers

[stage75]

Hello James,

Yes I declared all my wall (turbine and tank).

So if I mesh just the fluid area and not the turbine and tank, I would have just one mesh not two meshes? In this case I don't now how I can couplling ?

What I wanna know is how can I do to couple the two meshes using both subroutines ussatc.f90.

Mesh 1:

I have between FAce_1 .. ...and Face_31

Mesh 2,
I have between Face_37..... and Face_59

The all Faces are my groups (BCs)

In ussatc.f90 (SRC.1) I put :
d

Code: Select all

o ii = 1, nbcsat
  if (ii .eq. 1) then

    numsat = 2

    call defsat(numsat, namsat, 'all[]', ' ', ' ', 'Face_59', iwarns)

In ussatc.f90 (SRC.2) I put :

Code: Select all

do ii = 1, nbcsat

  if (ii .eq. 1) then

    numsat = 1
    call defsat(numsat, namsat, 'all[]', ' ', ' ', 'Face_31', iwarns)

It's right or note?

[stage75]

Hello Yvan and all,

As promised I deposed in this link my two meshes and subroutines oh (SRC.1 and SRC.2)

The fisrt subroutines in the link concerne SRC.1 and two meshes (fuse7.med-->correspond to the turbine and tank", then "cut10.med" -->correspond to the fluid volume) Then the is the four subroutines of (SRC.2).

I couldn't upload the meshes directly to the forum (they are heavy!!)

I created a hotmail account which I tabled files ( fichiers-fichiers@hotmail.fr and password = saturne) then you oppen the mail "FICHIERS SATURNE" and youclick in "acceder aux fichiers", THank's

Thank's, if you have a probleme to upload it tell me

[JamesMcNaughton]

Hi,

The coupling will either give the rotating part a Coriolis source term (icorio=1) or rotate the inner mesh (icorio=0) based on omegax/y/z.

At present you give Coriolis source term to the whole fluid volume - so it thinks the outer vanes are rotating too. The velocity vectors you plot are the relative velocity which makes it look like the fluid is rotating - in actual fact the turbine and vanes (tank) are.

What you want is to make the turbine rotate and the tank be stationary so you should set up the meshes as I have suggested.

I would suggest you start with a simple example to fully understand the coupling. Either create a 2D mesh as I described or maybe there is a simple example at EDF they can show you.

I hope that helps!

EDIT - I just saw your above post, hope someone at EDF has a look and can help you with your current course.

[stage75]

Thank you very much James,

When you said to do the mesh only the fluid domain and the rest not, I don't see how I will define the faces of the turbine and tank domain and then set my boundary conditions and to the coupling through these faces (because the boundary conditions are appplied after meshing!!).

Using sturne, meshes must be put in the menu "MESH" and I must specify their names in the "runcase" (if I understood correctly).

I will try your idea.

Yes I hope too that Yvan will take the time to look in detail at that. Then in totorial of Saturne there are no turning examples

[stage75]

Hi James,

As I said I cann't model the turbine without the mesh because it need two meshes to the coupling.

So this method doesn't work, I hope to have an answer of Yvan or another persons soon because I'm really stuck for almost 3 weeks!.

So if there are other proposals I am ready to test

I wish you all a very good weekend.

[JamesMcNaughton]

Hi,

For this type of coupling you should not couple at a boundary face but an an interface in the fluid domain. The interface is not a wall but an imaginary boundary between the rotating and stationary parts.

So in your image (http://code-saturne.org/forum/download/file.php?id=126) you will be meshing only the dark blue fluid region but as two meshes. Split the dark blue region by a cylinder that surrounds the inner blade.

Yes you will mesh the fluid and the boundaries but NOT the solid parts of the turbine.

When you couple the meshes the coupling faces you define in defsat are those of the cylindrical interface you have created. The other boundaries you have are turbine wall etc. These are NOT coupled. This is what I tried to explain with my drawing apologies if it was not clear.

So if you make your meshes as I describe and I think it will all work fine, if you have problems let me know.

Cheers,

James