modelStep3Staged
Extends from Modelica.Icons.Example (Icon for runnable examples), ThermofluidStream.Idealized.Utilities.IconInertanceNeglectOpenModelica (Icon for considerInertance = false (in OpenModelica)).
Information
In a third step, a second stage is added. The stages are thermally coupled by an intermediate heat exchanger.
The orange energy flow connector represents the heat transfer between condenser1 of the lower
cycle and evaporator2 of the upper cycle, see UsersGuide.EnergyFlow.
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This configuration corresponds to the classic cascade heat exchanger:
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The lower (low-temperature) stage rejects heat in
condenser1. -
The upper (high-temperature) stage absorbs this heat in
evaporator2and subsequently rejects it to the ambient incondenser2.
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The lower (low-temperature) stage rejects heat in
Index reduction requires considerInertance = false in Open Modelica,
see UsersGuide.InertanceNeglect.
Further documentation is available in the VaporCycle package.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Medium.Temperature | T_Evaporator1 | 253.15 | Evaporator 1 temperature |
| Medium.Temperature | T_Condensor2 | 323.15 | Condensor 2 temperature |
| SI.TemperatureDifference | dT_Intermediate | 10 | Temperature difference of intermediate heat exchanger |
| Medium.Temperature | T_Condensor1 | 1/2*(T_Evaporator1 + T_Condensor2) + 1/2*dT_Intermediate | Condensor 1 temperature |
| Medium.Temperature | T_Evaporator2 | T_Condensor1 - dT_Intermediate | Evaporator 2 temperature |
| Medium.AbsolutePressure | p_Evaporator1 | Medium.saturationPressure(T_Evaporator1) | Evaporator 1 pressure |
| Medium.AbsolutePressure | p_Condensor1 | Medium.saturationPressure(T_Condensor1) | Condensor 1 pressure |
| Medium.AbsolutePressure | p_Evaporator2 | Medium.saturationPressure(T_Evaporator2) | Evaporator 2 pressure |
| Medium.AbsolutePressure | p_Condensor2 | Medium.saturationPressure(T_Condensor2) | Condensor 2 pressure |
| Medium.SpecificEnthalpy | h_out_Evaporator1 | Medium.dewEnthalpy(Medium.setSat_T(T_Evaporator1)) | Evaporator 1 outlet specific enthalpy |
| Medium.SpecificEnthalpy | h_out_Condensor1 | Medium.bubbleEnthalpy(Medium.setSat_T(T_Condensor1)) | Condensor 1 outlet specific enthalpy |
| Medium.SpecificEnthalpy | h_out_Evaporator2 | Medium.dewEnthalpy(Medium.setSat_T(T_Evaporator2)) | Evaporator 2 outlet specific enthalpy |
| Medium.SpecificEnthalpy | h_out_Condensor2 | Medium.bubbleEnthalpy(Medium.setSat_T(T_Condensor2)) | Condensor 2 outlet specific enthalpy |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| ThermofluidStream.Idealized.Processes.Adiabatic | compressor1 | ||
| ThermofluidStream.DropOfCommons | dropOfCommons | ||
| ThermofluidStream.Idealized.Processes.Isobaric | condensor1 | ||
| ThermofluidStream.Idealized.Processes.Isenthalpic | valve1 | ||
| ThermofluidStream.Idealized.Processes.Isobaric | evaporator1 | ||
| ThermofluidStream.Idealized.Boundaries.LoopBreaker_m | loopBreaker1 | ||
| ThermofluidStream.Utilities.showRealValue | coefficientOfPerformance | ||
| ThermofluidStream.Idealized.Processes.Adiabatic | compressor2 | ||
| ThermofluidStream.Idealized.Processes.Isobaric | condensor2 | ||
| ThermofluidStream.Idealized.Processes.Isenthalpic | valve2 | ||
| ThermofluidStream.Idealized.Processes.Isobaric | evaporator2 | ||
| ThermofluidStream.Idealized.Boundaries.LoopBreaker | loopBreaker2 |
Contents
| Name | Description |
|---|---|
 Medium |
Revisions
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2026, by Raphael Gebhart (raphael.gebhart@dlr.de):
Initial version.