modelDesignOperation
Calculation of operation for nominal/design conditions
Information
This model calculates the nominal fuel power (W) for nominal conditions.
The nominal adiabatic efficiency (reference is the higher heating value (includes vaporization enthalpy)) comes from the SDF and depends on:
- Nominal return temperature (TRet_nominal)
- Nominale temperature difference (TSup_nominal-TRet_nominal)
- Nominal relative temperature difference (1)
- Nominal relative water mass flow (1)
Further assumptions are taken into account for nominal losses:
Thermal conductance is described by a fit 0.0465 * QNom/1000 +
4.9891 based on manufacturere data at a temperature difference
of 50 K to ambient
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.ThermalConductance | theCon | 0.0465*Q_flow_nominal/1000 + 4.9891 | Thermal conductance |
| Modelica.Units.SI.HeatFlowRate | nomEff | evaluate(extTabPEle, {TRet_nominal, TSup_nominal - TRet_nominal, 1, 1}, SDF.Types.InterpolationMethod.Linear, SDF.Types.ExtrapolationMethod.Hold) | Nominal efficiency |
| Modelica.Units.SI.HeatFlowRate | nomFueDem | (Q_flow_nominal + QLos_flow_nominal)/nomEff | Nominal fuel demand |
| Modelica.Units.SI.HeatFlowRate | QLos_flow_nominal | theCon*(TSup_nominal - TAmb) | Nominal heat losses |
| SDF.Types.ExternalNDTable | extTabPEle | SDF.Types.ExternalNDTable(4, SDF.Functions.readTableData(filename, "/Characteristic chart", "-", {"K", "K", "-", "-"})) | |
| Design | |||
| Modelica.Units.SI.HeatFlowRate | Q_flow_nominal | 50000 | Design thermal capacity |
| Modelica.Units.SI.Temperature | TSup_nominal | 273.15 + 80 | Design supply temperature |
| Modelica.Units.SI.Temperature | TRet_nominal | 273.15 + 60 | Design return temperature |
| Modelica.Units.SI.Temperature | TAmb | 273.15 + 20 | Ambient temperature for heat losses |
| Advanced | |||
| String | filename | ModelicaServices.ExternalReferences.loadResource("modelica://AixLib/Resources/Data/Fluid/BoilerCHP/BaseClasses/GenericBoiler/Boiler_Generic_Characteristic_Chart.sdf") | Filename for generic boiler curves |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Blocks.Interfaces.RealOutput | nomFueDemOut | Nominal fuel demand |
Contents
| Name | Description |
|---|---|
| evaluateprotected |
Revisions
-
June, 2023 by Moritz Zuschlag; David Jansen
First Implementation (see issue #1147)