Use this node to model inflow of moisture through a virtual domain, at inlet boundaries of moist air domains. The upstream moisture conditions (either vapor concentration custr or relative humidity
and temperature
Tustr) are known at the outer boundary of the virtual domain. The inflow condition is often similar to a moisture content condition. However using this condition the upstream vapor concentration is not strictly enforced at the inlet. The higher the flow rate, the smallest difference between the inlet concentration and upstream concentration. In case of moisture sources or moisture constraints close to the inlet boundary, the inflow condition induces a concentration profile that approaches to the concentration profile that would be obtained by computing the solution in the virtual domain upstream the inlet.
When the Concentrated species option is selected in the
Mixture type for moist air list, this condition may be rewritten as:
When Specify is set to
Relative humidity in the
Specify list, set both the
Upstream relative humidity 
and the
Upstream temperature Tustr from which the upstream vapor concentration can be defined:
For User Defined, enter values or expressions. Else, select any available input (like
Ambient temperature defined in an
Ambient Properties node under
Definitions).
Alternatively, choose Vapor concentration in the
Specify list, and set directly a value or expression for the
Upstream vapor concentration custr.
