.TransiEnt.Components.Boundaries.Gas.RealGasCompositionByWtFractions_stepVariation

Information

1. Purpose of model

Discrete variation of the mass fraction of one component of the real gas mixture. Example output for variation of xi[nc]:

2. Level of detail, physical effects considered, and physical insight

(Purely technical component without physical modeling.)

3. Limits of validity

If an entry is zero in xi_start, it will stay zero (unless it is the one varied). If an entry is zero, this causes that the sum of all entries is not 1 in all variations but the last one (nc).

4. Interfaces

Real output of mass composition vector xi[medium.nc-1] in [kg/kg]

5. Nomenclature

Mass composition vector xi[medium.nc-1]

xiNumber: Position in xi vector, this mass fraction will be varied.

6. Governing Equations

The last component of the mass composition vector is varied discretely with the defined stepsize. Every period the stepsize is added to the mass fraction of the last component:

If the last component (nc) is varied, the following holds:

As the sum of all mass fractions is equal to one, the sum of nc-1 mass fraction can be calculated via

(1)

for i in 1:nc-1.

For i in 1:nc-1 mass fractions, the following condition holds:

Therefore, considering eq. (1) the other mass fractions can be calculated via

for i in 1:nc-1.

If any other component is varied the new mass fractions can be calculated via

.

7. Remarks for Usage

(no remarks)

8. Validation

Tested in check model "TransiEnt.Components.Boundaries.Gas.Check.CheckStepVariationModels"

9. References

(no remarks)

10. Version History

Model created by Lisa Andresen (andresen@tuhh.de), Jan 2015

Modified by Lisa Andresen (andresen@tuhh.de), Dec 2016