Initial Values
The Initial Values node adds initial values for the mass fractions that can serve as an initial condition for a transient simulation, or as an initial guess for a nonlinear solver. If required, add additional Initial Values nodes from the Physics toolbar.
Initial Values
The initial mass fractions can be specified using a number of quantities. Select the type of input from the Mixture specification list. Select:
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Mass fractions (the default) to enter mass fractions (ω0,ω1 for example)
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Mole fractions to enter mole fractions (x0,ω1 for example)
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Molar concentrations (SI unit: mol/m3) to enter molar concentrations (c0,ω1 for example)
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Number densities (SI unit: 1/m3) to enter number densities (n0,ω1 for example)
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Densities (SI unit: kg/m3) to enter densities (ρ0,ω1 for example)
Enter a value or expression in the field for each species except for the one computed from the mass constraint.
Initial Mixture Density
When the selecting Molar concentrations, Number densities, or Densities are selected from the Mixture specification list, the should also be specified. Select Ideal gas or User defined from the Initial mixture density list.
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For Ideal gas, also specify the Initial pressure p0 and the Initial Temperature T0. Note that dependent variables solved for are evaluated to zero for initial values. When solving for pressure or temperature together with the mass fractions, apply the initial values from the corresponding interfaces here as well.
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For User defined, input a custom for the Initial mixture density ρm0.