Generate solid in inlet
 

Hello everyone,

I'm working on a project and I would like some help. I would like to generate a solid body like an inlet and to make it disappear like an outlet.

http://img15.hostingpics.net/pics/841932draw.png

In blue, there is my fluid flow and in grey my solid. I this problem, I must make this tube move for other problem which are not shown on this picture.
Could anyone tell me how to set this type of "flow" or even if it's possible?
Thank you

Do you think it could be a good simulation I tell my fluid it has an enormous viscosity and rewrite the others thermal characteristics?

Please tell what you think about this. Thank you