[minh khang]

Hi everyone.
I am running DTCHull tutorial in OF. At the outlet, in the tutorial, boundary condition for velocity is outletPhaseMeanVelocity.
outlet
{
type outletPhaseMeanVelocity;
alpha alpha.water;
Umean $Umean;
value $internalField;
}

Do you know what is "value" is used for? Is it the dummy value that used for visualization in Paraview?
My case is a little bit unusual as I have non uniform velocity at the inlet. For uniform velocity, it is easy to setup simulation and run without mass conservation issue. For non uniform inlet velocity, this BC finds a hard time to balance mass between inflow and outflow.