The Inlet node adds a boundary condition for the inflow (or outflow) perpendicular (normal) to the boundary. It has three options that can be used to specify inlet condition on a boundary, as follows:
Enter a value or expression for the Normal inflow velocity U0 (SI unit: m/s). A positive value of
U0 represents an inflow velocity. A negative value represents an outflow velocity. The inlet velocity boundary condition is implemented as;
where U0 is a value or expression for the specified inward (or outward) Darcy velocity. A positive value of the velocity
U0 corresponds to flow into the model domain whereas a negative value represents an outflow.
D is the elevation head which is set to zero for other than Subsurface Flow Module applications.
Use the Pressure option to specify the inlet pressure on a boundary. In many cases the distribution of pressure is known, giving a Dirichlet condition
p =
p0 where
p0 is a known pressure given as a number, a distribution, or an expression involving time,
t, for example. Enter a value or expression for the
Pressure p0(SI unit: Pa).
If you select Mass flow as the inlet condition, specify the total
Mass flow rate M0(SI unit: kg/s), or the
Pointwise mass flux N0(SI unit: kg/(m
2·s)).
With Mass flow rate boundary condition, positive values correspond to flow into the model domain:
where M0 is a value or expression for the specified inward (or outward) Darcy flux.
Pointwise mass flux boundary condition, positive values correspond to flow into the model domain:
where N0 is a value or expression for the specified inward (or outward) Darcy flux.
) and select Advanced Physics Options in the Show More Options dialog box.