Poisson eqn in ALE formulation

Wee

Hi,

I would like to find out whether if the poisson eqn in a fractional step scheme changes when the NS eqn is cast in the ALE (arbitrary langrange eulerian) formulation. I have seached thru the forums and it seems that some ppl suggested changing the velocity at the RHS to the relative velocity ie flow velocity - mesh velocity.

However, some others only mention changing the convective velocity to a relative one in the momentum equation.

Can someone give me a clue? Thanks you