Inlet
The Inlet boundary condition subnode is available from the context menu (right-click the Species parent node) or from the Physics toolbar, Attributes menu. This simplifies and orders the process of assigning boundary conditions for a large number of species in a model.
The Inlet subnode constrains one of the following quantities:
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The mass fraction: ω = ω0.
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The mole fraction: x = x0.
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The molar concentration (SI unit: mol/m3) c = c0.
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The number density, which describes the number of particles per volume (SI unit: 1/m3): n = n0.
Constraints of a quantity other than the mass fraction can only be used when all species are defined, as in the Inlet condition. The other quantities are composition dependent and therefore unambiguous only when all species are defined.
Inlet
Select the type of input from the Mixture specification list:
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Select Mass fraction (the default) to enter mass fractions (ω0, ω1, for example).
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Select Mole fraction to enter mole fractions (x0, ω1, for example).
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Select Molar concentration to enter molar concentrations (c0, ω1, for example).
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Select Number density to enter number densities (n0, ω1, for example).
Type the value or expression in the text fields for each species except the one computed from the mass constraint.
When using the Logarithmic form of the equations, setting a zero value for any of the options listed above results in an error when attempting to solve. To avoid the solver taking log(0) a positive, nonzero value must be entered.