modelDH_DirectConsumer

Multi port model of district heating consumer model.

Extends from dhcSim.DHC.Submodules.MultiPortModules.BaseClasses.BaseMultiPortModule.

Parameters

TypeNameDefaultDescription
IntegernLev (from LumpedMultiVolumeDeclarations)2Number of grid levels
Medium.SpecificEnthalpyh_start (from LumpedMultiVolumeDeclarations)Medium.specificEnthalpy(state = Medium.setState_pTX(p = p_start, T = T_start, X = X_start))
IntegeriLev11Grid connection of ports a1 and b1
IntegeriLev22Grid connection of ports a2 and b2
Booleanuse_HeatingCurvefalse=true, to use heating curve
Modelica.SIunits.TemperatureTNetRetSetMedium.T_defaultReturn temperature on primary side
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
Dynamics › Equations
Modelica.Fluid.Types.DynamicsenergyDynamics (from LumpedMultiVolumeDeclarations)Modelica.Fluid.Types.Dynamics.DynamicFreeInitialType of energy balance: dynamic (3 initialization options) or steady state
Modelica.Fluid.Types.DynamicsmassDynamics (from LumpedMultiVolumeDeclarations)energyDynamicsType of mass balance: dynamic (3 initialization options) or steady state
Modelica.Fluid.Types.DynamicssubstanceDynamics (from LumpedMultiVolumeDeclarations)energyDynamicsType of independent mass fraction balance: dynamic (3 initialization options) or steady state
Modelica.Fluid.Types.DynamicstraceDynamics (from LumpedMultiVolumeDeclarations)energyDynamicsType of trace substance balance: dynamic (3 initialization options) or steady state
Initialization
Modelica.SIunits.AbsolutePressurep_start (from LumpedMultiVolumeDeclarations)fill(Medium.p_default, nLev)Start value of pressure
Modelica.SIunits.TemperatureT_start (from LumpedMultiVolumeDeclarations)fill(Medium.T_default, nLev)Start value of temperature
Medium.MassFractionX_start (from LumpedMultiVolumeDeclarations)fill(Medium.X_default, nLev)Start value of mass fractions m_i/m
Medium.ExtraPropertyC_start (from LumpedMultiVolumeDeclarations)fill(0, nLev, Medium.nC)Start value of trace substances
Medium.ExtraPropertyC_nominal (from LumpedMultiVolumeDeclarations)fill(1E-2, nLev, Medium.nC)Nominal value of trace substances. (Set to typical order of magnitude.)
Dynamics
RealmSenFac (from LumpedMultiVolumeDeclarations)1Factor for scaling the sensible thermal mass of the volume
Modelica.SIunits.Timetau (from BaseMultiPortModule)10Time constant at nominal flow for dynamic energy and momentum balance
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 BaseMultiPortModule)10Nominal mass flow rate
Assumptions
BooleanallowFlowReversal (from BaseMultiPortModule)true= true to allow flow reversal, false restricts to design direction (port_a -> port_b)
Advanced
Medium.MassFlowRatem_flow_small (from BaseMultiPortModule)1E-4*abs(m_flow_nominal)Small mass flow rate for regularization of zero flow
Advanced › Diagnostics
Booleanshow_T (from BaseMultiPortModule)false= true, if actual temperature at port is computed
Nominal Conditions
dhcSim.Data.SystemTemperaturessysTem
Table data
StringtableName"table"Table name
StringfileName"NoName"File name

Connectors

TypeNameDefaultDescription
Modelica.Fluid.Interfaces.FluidPorts_aports_a (from BaseMultiPortModule)Fluid connector a (positive design flow direction is from port_a to port_b)
Modelica.Fluid.Interfaces.FluidPorts_bports_b (from BaseMultiPortModule)Fluid connector b (positive design flow direction is from port_a to port_b)
Modelica.Blocks.Interfaces.RealOutputQ_flow_out
Modelica.Blocks.Interfaces.RealOutputdp_out
Modelica.Blocks.Interfaces.RealInputTAmb_in

Components

TypeNameDefaultDescription
FourPortModules.DistrictHeating.Consumer.DH_DirectHeatConsumeractCon
Modelica.Blocks.Sources.RealExpressionTAmb_expr