modelBoilerNoControl

Boiler model with physics only

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

Information

Overview

A boiler model consisting of physical components.The efficiency is based on the part load rate and the inflow water temperature.


Assumptions for predefined parameter values (based on Vissmann data cheat 5811009):

G: a heat loss of 0.3 % of nominal power at a temperature difference of 50 K to ambient is assumed.

C: factor C/Q_nom 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.

  • September 19, 2019  by Alexander Kümpel:
    First implementation

Parameters

TypeNameDefaultDescription
Modelica.Units.SI.ThermalConductanceG0.003*Q_nom/50Constant thermal conductance to environment(G=Q_loss/dT)
Modelica.Units.SI.HeatCapacityC1.5*Q_nomHeat capacity of metal (J/K)
Modelica.Units.SI.VolumeVparamBoiler.volumeVolume
Modelica.Units.SI.PowerQ_nomparamBoiler.Q_nomNominal heating power
Real[:,2]etaLoadBasedparamBoiler.etaTable matrix for part load based efficiency (e.g. [0,0.99; 0.5, 0.98; 1, 0,97])
Real[:,2]etaTempBased[293.15, 1.09; 303.15, 1.08; 313.15, 1.05; 323.15, 1.; 373.15, 0.99]Table matrix for temperature based efficiency
General › Boiler type
AixLib.DataBase.Boiler.General.BoilerTwoPointBaseDataDefinitionparamBoilerParameters for Boiler

Components

TypeNameDefaultDescription
Modelica.Thermal.HeatTransfer.Components.HeatCapacitorinternalCapacityBoiler thermal capacity (dry weight)
Modelica.Thermal.HeatTransfer.Components.ThermalConductorConductanceToEnvThermal resistance of the boiler casing
Modelica.Blocks.Math.ProductQgasCalculationCalculate gas usage
Modelica.Blocks.Nonlinear.LimiterlimiterLimits the rel power between 0 and 1
Modelica.Blocks.Sources.RealExpressionNominalGasConsumptionNominal gas power
Modelica.Blocks.Interfaces.RealOutputfuelPowerConnector of Real output signal
Modelica.Blocks.Interfaces.RealOutputthermalPowerValue of Real output
Modelica.Blocks.Interfaces.RealInputu_relRelative gas power [0,1]
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_bT_ambHeat port for heat losses to ambient
Modelica.Blocks.Tables.CombiTable1DvefficiencyTableLoadDependingTable with efficiency parameters
Modelica.Blocks.Math.ProductQflowCalculationCalculation of the produced heatflow
Modelica.Blocks.Interfaces.RealOutputT_outOutflow temperature of the passing fluid
Modelica.Blocks.Interfaces.RealOutputT_inInflow temperature of the passing fluid
Modelica.Blocks.Math.ProductetaCalculationcalculates the efficiency of the boiler
Modelica.Blocks.Tables.CombiTable1DvefficiencyTableLoadDepending1Table with efficiency parameters