modelBoilerGeneric

Generic performance map based boiler

Extends from AixLib.Fluid.BoilerCHP.BaseClasses.PartialHeatGenerator.

Information

Overview

The model differs between DesignOperation and OffDesignOperation.

In DesignOperation for nominal conditions the (max) fuel power is estimated. The OffDesignOperation fuel consumption is estimated via firing rate.

During operation, the transferred heat flow is estimated with respect to actual efficiency within a performance map.


Further assumptions are used:

  • The quadratic coefficient coeffPresLoss is described by a fit-function from manufacturer data.
  • The volume vol.V bases on a fit from manufacturer data.
  • G: Thermal conductance is described by a fit 0.0465 * QNom/1000 + 4.9891 from manufacturere data at a temperature difference of 50 K to ambient
  • C: Factor C/QNom is in range of 1.2 to 2 for boilers with nominal power between 460 kW and 80 kW (with c of 500J/kgK for steel). Thus, a value of 1.5 is used as default. (see AixLib.Fluid.BoilerCHP.BoilerNoControl)

Parameters

TypeNameDefaultDescription
Nominal condition
Modelica.Units.SI.HeatFlowRateQ_flow_nominalDesign thermal capacity
Modelica.Units.SI.TemperatureTSup_nominal353.15Design supply temperature
Modelica.Units.SI.TemperatureTRet_nominal333.15Design return temperature
Advanced
StringfilenameModelicaServices.ExternalReferences.loadResource("modelica://AixLib/Resources/Data/Fluid/BoilerCHP/BaseClasses/GenericBoiler/Boiler_Generic_Characteristic_Chart.sdf")Filename for generic boiler curves

Components

TypeNameDefaultDescription
Modelica.Thermal.HeatTransfer.Components.HeatCapacitorintCapBoiler thermal capacity (dry weight)
AixLib.Fluid.BoilerCHP.BaseClasses.OffDesignOperationoffDesignOperationCalculate efficiency in off design operation
Modelica.Thermal.HeatTransfer.Components.ThermalConductorconToEnvThermal resistance of the boiler casing
Modelica.Thermal.HeatTransfer.Sources.FixedTemperatureTEnvFixTemperature of environment around the boiler to account for heat losses
Modelica.Thermal.HeatTransfer.Sensors.HeatFlowSensorheaFloSenSensor to measure heatflow of heatlosses
AixLib.Controls.Interfaces.BoilerControlBusboiBusSignal bus for the boiler
Modelica.Thermal.HeatTransfer.Sensors.TemperatureSensorTSupMeaMeasurement of supply/volume temperature
AixLib.Fluid.BoilerCHP.BaseClasses.DesignOperationdesignOperationCalculate design fuel power
Modelica.Blocks.Math.ProductfuePowFuel power calculation
Modelica.Blocks.Math.ProductthePowThermal power calculation

Revisions

  • June, 2023 by Moritz Zuschlag; David Jansen
    First Implementation (see issue #1147)