Mass Flux

Use the Mass Flux feature to specify the mass flux into or out of the model domain through some of its boundaries. It is often possible to determine the mass flux from the pumping rate or from measurements. With the Mass Flux boundary condition, positive values correspond to flow into the model domain

–n u = N0

where N0 is a value or expression for the inward (or outward) Darcy’s flux that is specified.

B O U N D A R Y S E L E C T I O N

From the Selection list, choose the boundaries to apply an inward or outward mass flux.

M A S S F L U X A N D S A T U R A T I O N

Enter a value or expression for the Inward mass flux N0 (SI unit: kg/(m2·s)). A positive value of N0 represents an inward mass flux. This can also be an outward mass flux.

Enter a value or expression for the Saturation fluid 1 s1 (a dimensionless number between 0 and 1) in the mass flux. The default value is 0.

Inflow Boundary

The Inflow Boundary feature adds a boundary condition for the inflow (or outflow) perpendicular (normal) to the boundary:

–n u = s1 1 + s2 1 U0

where U0 is a value or expression for the inward (or outward) Darcy’s velocity that is specified. A positive value of the velocity U0 corresponds to flow into the model domain; a negative value represents an outflow.

B O U N D A R Y S E L E C T I O N

From the Selection list, choose the boundaries to apply an inflow or outflow velocity.

I N F L O W B O U N D A R Y

Enter a value or expression for the Inward velocity U0 (SI unit: m/s). A positive value of U0 represents an inflow velocity. This can also be an outward velocity.

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