Gas Boundary Condition Equations
In addition to the boundary conditions for the liquid, specify boundary conditions for the gas on Wall, Inlet, Outlet, and Interior Wall nodes. Select a Gas Boundary Condition:
Gas Concentration
Using this boundary condition, specify the effective gas density.
Gas Outlet
This boundary condition is appropriate for boundaries where the gas phase flows outward with the gas velocity, ug, at the boundary.
Gas Flux
Using this boundary condition, specify the gas mass flux through the boundary:
Symmetry
This boundary condition, which is useful on boundaries that represent a symmetry line for the gas flow, sets the gas flux through the boundary to zero:
No Gas Flux
This boundary condition represents boundaries where the gas flux through the boundary is zero:
In walls moving with a boundary velocity ubnd, the gas flux through the boundary is: