If the Transient with Phase Initialization (

) study is being used, then, for the initialization to work, it is crucial that there are two
Initial Values nodes. One of the Initial Values nodes should use
Specify phase: Fluid 1 (ϕ = 0) and the other
Specify phase: Fluid 2 (ϕ = 1). The initial fluid-fluid interface is then automatically placed on all interior boundaries between both phases. The smooth initialization is not used in domains with
User defined initial values.