modelMassFractionModifier
Mass fraction modifier
Extends from ThermofluidStream.Interfaces.SISOFlow (Base Model with basic flow eqautions for SISO).
Information
Process to achieve a change in composition. Further assumptions:
- Isobaric:
p_out = p_in - Isothermal:
T_out = T_in. This can lead to errors in the two-phase region, where temperature alone does not uniquely define the thermodynamic state.. - Steady-state conditions:
dE_sys/dt = 0, dm_sys/dt = 0
The following quantities can be specified either as parameters or as time-varying input signals:
- Difference in mass fractions:
dXi = X_out - X_in - Outlet mass fractions:
X_out
See the example Tests.Processes.MassFractionModifier.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| String | instanceName (from DropOfCommonsPlus) | getInstanceName() | Instance name |
| Layout | |||
| Boolean | displayInstanceName (from DropOfCommonsPlus) | dropOfCommons.displayInstanceNames | = true, if instance name is displayed |
| Boolean | displayParameters (from DropOfCommonsPlus) | dropOfCommons.displayParameters | = true, if displaying parameters is enabled |
| Advanced | |||
| Boolean | considerInertance (from SISOFlow) | dropOfCommons.considerInertance | =true, if transient momentum (inertance) term is considered; disable only for advanced use |
| Utilities.Units.Inertance | L (from SISOFlow) | dropOfCommons.L | Inertance |
| StateSelect | m_flowStateSelect (from SISOFlow) | StateSelect.default | State selection for mass flow rate |
| Boolean | clip_p_out (from SISOFlow) | = false, if dr_corr=0 (correction of inertial pressure difference) | |
| Medium.AbsolutePressure | p_min (from SISOFlow) | dropOfCommons.p_min | Minimum steady-state output pressure |
| Initialization › Mass flow rate | |||
| InitializationMethods | initM_flow (from SISOFlow) | ThermofluidStream.Utilities.Types.InitializationMethods.none | Initialization method for mass flow rate |
| SI.MassFlowRate | m_flow_0 (from SISOFlow) | 0 | Initial value for mass flow rate |
| Utilities.Units.MassFlowAcceleration | m_acceleration_0 (from SISOFlow) | 0 | Initial value for derivative of mass flow rate |
| Specification | |||
| OutletSpecification | outletSpec | ThermofluidStream.Idealized.Types.OutletSpecification.Composition.MassFractionsDifference | Quantity used to define the outlet state |
| ValueSpecification | outletValueSpec | ThermofluidStream.Types.ValueSpecification.Fixed | Specifies whether the quantity is fixed or prescribed |
| ThermofluidStream.Units.MassFractionDifference[Medium.nXi] | dXi_fixed | fill(0, Medium.nXi) | Fixed difference in mass fractions (dXi = Xi_out - Xi_in) |
| Medium.MassFraction[Medium.nXi] | Xi_out_fixed | Medium.X_default[1:Medium.nXi] | Fixed outlet mass fractions |
| Layout › Display parameters | |||
| Boolean | showOutletSpecification | true | = true to show the fixed outlet specification value (either dXi_fixed or Xi_out_fixed) |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Inlet | inlet (from SISOFlow) | ||
| Outlet | outlet (from SISOFlow) | ||
| Modelica.Blocks.Interfaces.RealInput[Medium.nXi] | outletSpec_prescribed | Prescribed outlet specification [kg/kg] |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| SI.MassFlowRate | m_flow (from SISOFlow) | inlet.m_flow | Mass flow rate |
| SI.Pressure | dr_corr (from SISOFlow) | Correction of inertial pressure difference | |
| SI.Pressure | dp (from SISOFlow) | Pressure difference | |
| Medium.AbsolutePressure | p_in (from SISOFlow) | Medium.pressure(inlet.state) | Inlet pressure |
| Medium.SpecificEnthalpy | h_in (from SISOFlow) | Medium.specificEnthalpy(inlet.state) | Inlet specific enthalpy |
| Medium.MassFraction[Medium.nXi] | Xi_in (from SISOFlow) | Medium.massFraction(inlet.state) | Inlet mass fractions |
| Medium.AbsolutePressure | p_out (from SISOFlow) | Outlet pressure | |
| Medium.SpecificEnthalpy | h_out (from SISOFlow) | Outlet specific enthalpy | |
| Medium.MassFraction[Medium.nXi] | Xi_out (from SISOFlow) | Outlet mass fractions | |
| ThermofluidStream.Units.MassFractionDifference[Medium.nXi] | dXi | Difference in mass fractions | |
| Medium.Temperature | T_in | Medium.temperature(inlet.state) | Inlet temperature |
Revisions
-
2026-08, by Silvan Keim (silvan.keim@dlr.de):
Improved icon. -
2026, by Raphael Gebhart (raphael.gebhart@dlr.de):
Initial version.