[LukeFullard]

Hi,

I would like to simulate a tube (pipe) which is deformable. Initially the (viscoelastic) fluid inside the pipe will be stationary, no velocity or momentum. I want to then squeeze the tube so that fluid exits one or both ends of the pipe. What boundary conditions could I set in this case? Further, if i then release the tube I want to allow fluid to flow back into the tube (i.e. backflow)

I was thinking of setting inlet and outlet velocity to zero.

If I defined a stationary velocity profile at the inlet and outlets and then compressed my tube (i.e. generating fluid movement in the initially stationary fluid) does Polyflow force my boundaries to still be at the stationary velocity profile? How about Fluent?

I assume there is a way to update the velocity of the boundary based upon the fluid movement in the domain? i.e. if after a timestep some fluid exits the domain, that boundary condition there could be updated so that the velocity at the boundary has the velocity of the exiting fluid?

I thought pressure boundary conditions could be useful too (i.e. set atmospheric pressure at both ends) but I don't think Polyflow is capable of this, although I think Fluent is.

Help appreciated, I am new to CFD and viscoelastic flows.

Thanks all