modelPartialCarnot
Model with components for Carnot efficiency calculation
Information
Partial model for equations and componenents used in both heat pump and chiller with the Carnot approach.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Boolean | useForChi | =false to use in heat pump models | |
| Nominal condition | |||
| Real | etaCarnot_nominal | 0.3 | Constant Carnot effectiveness |
| Efficiency | |||
| Boolean | use_constAppTem | false | =true to fix approach temperatures at nominal values. This can improve simulation speed |
| Modelica.Units.SI.TemperatureDifference | TAppCon_nominal | Temperature difference between refrigerant and working fluid outlet in condenser | |
| Modelica.Units.SI.TemperatureDifference | TAppEva_nominal | Temperature difference between refrigerant and working fluid outlet in evaporator | |
| Advanced | |||
| Modelica.Units.SI.TemperatureDifference | dTCarMin | 5 | Minimal temperature difference, used to avoid division errors |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Blocks.Sources.RealExpression | reaCarnotCOP | Internal calculation of Carnot COP | |
| Modelica.Blocks.Math.MultiProduct | proQUse_flow | Calculate QUse_flow | |
| Modelica.Blocks.Math.Product | proPEle | Calculate electrical power consumption | |
| Modelica.Blocks.Sources.Constant | constPEle | Constant electrical power consumption | |
| Modelica.Blocks.Routing.RealPassThrough | pasThrYMea | From signal bus | |
| Modelica.Units.SI.Temperature | TUseSidAct | if useForChi then TEvaAct else TConAct | Useful side refrigerant temperature |
| Modelica.Units.SI.Temperature | TConAct | pasThrTCon.y + TAppCon | Refrigerant condensation temperature |
| Modelica.Units.SI.Temperature | TEvaAct | pasThrTEva.y - TAppEva | Refrigerant evaporation temperature |
| Modelica.Units.SI.TemperatureDifference | TAppCon | if use_constAppTem then TAppCon_nominal else TAppCon_nominal*QCon_flow_internal/QCon_flow_nominal | Condenser approach temperature |
| Modelica.Units.SI.TemperatureDifference | TAppEva | if use_constAppTem then TAppEva_nominal else TAppEva_nominal*QEva_flow_internal/QEva_flow_nominal | Evaporator approach temperature |
| Modelica.Blocks.Sources.Constant | constZer | Constant zero value if off | |
| Modelica.Blocks.Logical.Switch | swiPEle | If device is off, no heat exchange occurs | |
| Modelica.Blocks.Logical.Switch | swiQUse | If device is off, no heat exchange occurs | |
| Modelica.Blocks.Routing.RealPassThrough | pasThrTEva | Evaporator outlet pass through | |
| Modelica.Blocks.Routing.RealPassThrough | pasThrTCon | Condenser outlet pass through | |
| Modelica.Blocks.Sources.RealExpression | reaCarnotEff | Internal calculation of Carnot effectiveness |
Revisions
-
November 17, 2025, by Michael Wetter:
Corrected typo in annotation.
This is for Buildings, #4406. -
May 2, 2025, by Michael Wetter:
SetEvaluate=trueforuse_constAppTem. This is a structural parameter, if evaluated during translation, it has shown to remove a 2x2 nonlinear system of equations to compute the approach temperatures.
This is for IBPSA, #2005. -
October 2, 2022 by Fabian Wuellhorst:
First implementation (see issue #1576)