I am having problems understanding the boundary conditions of the problem described in this paper on researchgate
Essentially the problem consists of a one dimensional fluid chamber in contact with a piston on the right hand side. The problem makes use of the ALE mesh moving technique. The ALE is moved in such a way that the elements remain equidistant, so essentially the mesh velocity varies linearly at all times.
My understanding is that on the left hand side, the velocity of the fluid and the mesh are set to zero whilst the pressure and density are linearly interpolated. On the right hand side, the fluid and mesh velocities are set equal to the piston velocity whilst pressure and density are interpolated.
I would appreciate some guidance on those.