Vapor Content
Use this node to specify the moisture conditions on exterior boundaries. This node always constrains the vapor concentration, but different inputs (relative humidity and temperature, vapor concentration, or vapor mass fraction) can be specified.
Vapor Content
The equation for this condition is
The vapor concentration c0, the relative humidity ϕw,0, and the vapor mass fraction ω0 are always available at the boundary. They have different expressions depending on the chosen inputs.
When Specify is set to Relative humidity, the vapor concentration c0 is defined as
where ϕw,0 and T0 are the prescribed relative humidity and temperature on the boundary. For User Defined, enter values or expressions. Else, select any available input (like Ambient temperature defined in an Ambient Properties node under Definitions). The vapor mass fraction is defined as
Alternatively, choose Vapor concentration in the Specify list and set directly the Vapor concentration c0. The relative humidity on the boundary is then deduced
and the vapor mass fraction as well
Finally, choose Vapor mass fraction in the Specify list to set directly ω0. The vapor concentration on the boundary is then deduced
and the relative humidity as well
Location in User Interface
Context Menus
Ribbon
Physics tab with Hygroscopic Porous Medium > Moist Air selected: