code_saturne User's Forum

Dear developers and users,
I'd like to simulate a rectangular channel flow. Half way of the channel a hexangular body is rotating around an axis perpendicular to the main channel. Thus, the cross section of the channel is changing in time. My question: Am I able to simulate it with Code Saturne ??? I thought about using the possibility of moving walls with the ALE method. If yes, which user subroutines you advise me to use?
Best regards,
Thomas Aumeier  
 
 

Dear Thomas,
 
This cannot be done at the moment with Code_Saturne version 1.3.3 or 2.0-beta2.
The ALE method is indeed used to have the mesh moving, depending on the displacements at the walls (for example), but you will not be able to use it in your case because of the rotation of the body: in case of rotation, the cells could overlap and their volume become negative...
You could also think of using sliding walls, but this would work only if the body was a cylinder: the sliding velocity has to be tangential to the wall, and the geometry remain the same along the calculation (this is not your case due to the hexaedron form of your body).
 
Nonetheless, next version of Code_Saturne (2.0-rc1) will  be released (soon) with an experimental feature (i.e. not validated) of code/code coupling. You could then imagine a first mesh around your body (this mesh will rotate) and a second one around this first one for the channel flow (this mesh will be fixed).
I'm not sure to be clear enough in my explanations, so ask me for more details if needed! And if you think this solution could be useful for you, I shall explain to you more precisely how it can be done.
 
Best regards,
David

Dear David,
ok, I think know what you mean with the code/code coupling. I guess you 'll specify an interface between the two meshes that exchange data after each time step. I'll wait for the new release of CS and if there are questions I ask you later.
Best regards
Thomas

Dear Support and users,
Sorry to dig up this topic, but I am interested by the possibility of simulating rotating objects. And I don't really see how to do that,  I would like to test this on a simple geometry (like a cubic object in a channel flow).
Could you help me? (I use Code_Saturne 2.0-rc1 by the way.)
Best Regards,
Stéphane