modelDH_DirectHeatConsumer

Four port model of district heating consumer model.

Extends from Buildings.Fluid.Interfaces.TwoPortFlowResistanceParameters (Parameters for flow resistance for models with two ports), dhcSim.DHC.Submodules.FourPortModules.Interfaces.FourPortModulesParameters (Record of needed parameters for four port modules), dhcSim.DHC.Submodules.FourPortModules.BaseClasses.BaseModule, dhcSim.DHC.Submodules.FourPortModules.BaseClasses.ExternalProfiles, dhcSim.DHC.Submodules.FourPortModules.BaseClasses.SupplyReturnTemperatures.

Parameters

TypeNameDefaultDescription
IntegernSpl1 (from BaseModule)Number of splitters between port_a1 and port_b1
IntegernSpl2 (from BaseModule)Number of splitters between port_a2 and port_b2
Booleanuse_HeatingCurvefalse=true, to use heating curve
Modelica.SIunits.TemperatureTNetRetSetMedium.T_defaultReturn temperature if use_HeatingCurve=false
Modelica.SIunits.TemperatureTGradHX5Graedigkeit of internal heat exchanger if use_HeatingCurve=true
RealProfCtrl1Control parameter for profile usage
Modelica.SIunits.MassFlowRatem_flow_min0.02*m_flow_nominalMinimum mass flow rate of consumer
Flow resistance
BooleancomputeFlowResistance (from TwoPortFlowResistanceParameters)true=true, compute flow resistance. Set to false to assume no friction
Booleanfrom_dp (from TwoPortFlowResistanceParameters)false= true, use m_flow = f(dp) else dp = f(m_flow)
BooleanlinearizeFlowResistance (from TwoPortFlowResistanceParameters)false= true, use linear relation between m_flow and dp for any flow rate
RealdeltaM (from TwoPortFlowResistanceParameters)0.1Fraction of nominal flow rate where flow transitions to laminar
Nominal condition
Modelica.Units.SI.PressureDifferencedp_nominal (from TwoPortFlowResistanceParameters)Pressure difference
Modelica.SIunits.MassFlowRatem_flow_nominal (from FourPortModulesParameters)Nominal mass flow rate
Assumptions
BooleanallowFlowReversal (from FourPortModulesParameters)true= true to allow flow reversal, false restricts to design direction (port_a -> port_b)
Advanced › Diagnostics
Booleanshow_T (from FourPortModulesParameters)false= true, if actual temperature at port is computed
Advanced
Modelica.SIunits.MassFlowRatem_flow_small (from FourPortModulesParameters)1E-4*abs(m_flow_nominal)Small mass flow rate for regularization of zero flow
Dynamics › Equations
Modelica.Fluid.Types.DynamicsenergyDynamics (from BaseModule)Modelica.Fluid.Types.Dynamics.DynamicFreeInitialType of energy balance: dynamic (3 initialization options) or steady state
Dynamics › Nominal condition
Modelica.SIunits.Timetau (from BaseModule)10Time constant at nominal flow for dynamic energy and momentum balance
Initialization › Side 1
Medium.AbsolutePressurep_start_1 (from BaseModule)Medium.p_defaultStart value of pressure
Medium.TemperatureT_start_1 (from BaseModule)Medium.T_defaultStart value of temperature
Medium.MassFraction[Medium.nX]X_start_1 (from BaseModule)Medium.X_defaultStart value of mass fractions m_i/m
Medium.ExtraProperty[Medium.nC]C_start_1 (from BaseModule)fill(0, Medium.nC)Start value of trace substances
Medium.ExtraProperty[Medium.nC]C_nominal_1 (from BaseModule)fill(1E-2, Medium.nC)Nominal value of trace substances. (Set to typical order of magnitude.)
Initialization › Side 2
Medium.AbsolutePressurep_start_2 (from BaseModule)Medium.p_defaultStart value of pressure
Medium.TemperatureT_start_2 (from BaseModule)Medium.T_defaultStart value of temperature
Medium.MassFraction[Medium.nX]X_start_2 (from BaseModule)Medium.X_defaultStart value of mass fractions m_i/m
Medium.ExtraProperty[Medium.nC]C_start_2 (from BaseModule)fill(0, Medium.nC)Start value of trace substances
Medium.ExtraProperty[Medium.nC]C_nominal_2 (from BaseModule)fill(1E-2, Medium.nC)Nominal value of trace substances. (Set to typical order of magnitude.)
Table data
StringtableName (from ExternalProfiles)"table"Table name
StringfileName (from ExternalProfiles)"NoName"File name
Integer[:]columns (from ExternalProfiles){2, 3, 4}Columns of table to be interpolated, 2=QFlow, 3=TNetSup, 4=TEva
Nominal Conditions
dhcSim.Data.SystemTemperaturessysTem (from SupplyReturnTemperatures)

Connectors

TypeNameDefaultDescription
Modelica.Fluid.Interfaces.FluidPort_aport_a1 (from BaseModule)Fluid connector a1 (positive design flow direction is from port_a1 to port_b1)
Modelica.Fluid.Interfaces.FluidPort_bport_b1 (from BaseModule)Fluid connector b1 (positive design flow direction is from port_a1 to port_b1)
Modelica.Fluid.Interfaces.FluidPort_aport_a2 (from BaseModule)Fluid connector a2 (positive design flow direction is from port_a2 to port_b2)
Modelica.Fluid.Interfaces.FluidPort_bport_b2 (from BaseModule)Fluid connector b2 (positive design flow direction is from port_a2 to port_b2)
Modelica.Blocks.Interfaces.RealInputTAmb_in (from SupplyReturnTemperatures)
Modelica.Blocks.Interfaces.RealOutputQ_flow_out
Modelica.Blocks.Interfaces.RealOutputdp_out

Components

TypeNameDefaultDescription
Buildings.Fluid.FixedResistances.Junctionspl2 (from BaseModule)
Buildings.Fluid.FixedResistances.Junctionspl1 (from BaseModule)
Modelica.Blocks.Sources.CombiTimeTableloadTable (from ExternalProfiles)
Modelica.Blocks.Sources.RealExpressionQFlow_table (from ExternalProfiles)
dhcSim.Controls.SetPoints.HotWaterTemperatureResethotWatRes (from SupplyReturnTemperatures)
Modelica.SIunits.TemperatureTRetIntInternal calculated return temperature of consumer on grid side
TwoPortModules.CooleractCon