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Mass Transfer
Use the Mass Transfer node to include mass transfer from the dispersed phase to the continuous phase.
Mass Transfer
Select a Mass transfer model — User defined (the default), Nonequilibrium model, or Two-film theory. For User defined enter a value or expression for the Mass transfer from dispersed to continuous phase mdc (SI unit: kg/(m3·s)). The default is 0 kg/(m3·s).
Nonequilibrium Model
For Nonequilibrium model enter values or expressions for each of the following:
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Equilibrium volume fraction in dispersed phase eq. The default is 0.
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Inverse time scales fc and fd (SI unit: 1/s). The default is 0 s-1.
The mass transfer is modeled as
Two-Film Theory
For Two-film theory enter values or expressions for each of the following:
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Mass transfer coefficient k (SI unit: m/s). The default is 0 m/s.
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Species concentration in dispersed phase cd (SI unit: mol/m3). The default is 0 mol/m3.
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Species concentration in continuous phase cc (SI unit: mol/m3). The default is 0 mol/m3.
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Molecular weight of species M (SI unit: kg/mol). The default is 0 kg/mol.
The mass transfer is modeled as
where k denotes the mass transfer rate, and cd and cc are the species concentrations in the dispersed and the continuous phase, respectively. M is the species’ molecular weight, and a is the interfacial area per unit volume between the two phases. The Mass transfer model — Two-film theory is available when the Solve for interfacial area check box is selected (under the Physical Model section).