Buildings.DHC.Loads.Heating

This package contains models for loads used in district heating systems.

Information

This package contains models of building loads that are used to build example models of district heating systems.

Extends from Modelica.Icons.VariantsPackage (Icon for package containing variants).

Package Content

Name	Description
BuildingTimeSeriesWithETS	Model of a building with loads provided as time series, connected to an ETS for heating
Examples
BaseClasses	Package with base classes that are used by multiple models

Buildings.DHC.Loads.Heating.BuildingTimeSeriesWithETS

Model of a building with loads provided as time series, connected to an ETS for heating

Buildings.DHC.Loads.Heating.BuildingTimeSeriesWithETS

Information

This model is composed of a direct controlled energy transfer station model for heating Buildings.DHC.ETS.Heating.Direct connected to a simplified building model Buildings.DHC.Loads.BaseClasses.BuildingTimeSeries where the space heating loads are provided as time series.

Extends from BaseClasses.PartialBuildingWithETS (Partial model with ETS model for heating and partial building model).

Parameters

Type	Name	Default	Description
replaceable package MediumSer		Water	Service side medium
replaceable package MediumSerHea_a		Water	Service side medium at heating inlet
replaceable package MediumBui		Water	Building side medium
PressureDifference	dpSup	5000	Pressure drop in the ETS supply side [Pa]
PressureDifference	dpRet	5000	Pressure drop in the ETS return side [Pa]
String	filNam		Library path of the file with thermal loads as time series
Configuration
Integer	nPorts_heaWat	1	Number of heating water fluid ports
Integer	nPorts_chiWat	0	Number of chilled water fluid ports
Scaling
Real	facMul	1	Multiplier factor
Nominal condition
MassFlowRate	mBui_flow_nominal	QHea_flow_nominal/(cp*dT_nom...	Nominal mass flow rate [kg/s]
TemperatureDifference	dT_nominal	10	Water temperature drop/increase accross load and source-side HX (always positive) [K]
PID controller
SimpleController	controllerType	Modelica.Blocks.Types.Simple...	Type of controller
Real	k	0.1	Gain of controller [1]
Time	Ti	60	Time constant of integrator block [s]
Time	Td	0.1	Time constant of derivative block [s]
Real	yMax	1	Upper limit of output
Real	yMin	0	Lower limit of output
Nominal conditions
Temperature	THeaWatSup_nominal	50 + 273.15	Heating water supply temperature [K]
Assumptions
Boolean	allowFlowReversalSer	false	Set to true to allow flow reversal on service side
Boolean	allowFlowReversalBui	false	Set to true to allow flow reversal on building side
Dynamics
Conservation equations
Dynamics	energyDynamics	Modelica.Fluid.Types.Dynamic...	Type of energy balance
Pump
Boolean	use_inputFilter	false	= true, if pump speed is filtered with a 2nd order CriticalDamping filter

Connectors

Type	Name	Description
FluidPort_a	port_aSerAmb	Fluid connector for ambient water service supply line
FluidPort_b	port_bSerAmb	Fluid connector for ambient water service return line
FluidPort_a	port_aSerHea	Fluid connector for heating service supply line
FluidPort_b	port_bSerHea	Fluid connector for heating service return line
FluidPort_a	port_aSerCoo	Fluid connector for cooling service supply line
FluidPort_b	port_bSerCoo	Fluid connector for cooling service return line
Bus	weaBus	Weather data bus
output RealOutput	QHea_flow	Total heating heat flow rate transferred to the loads (>=0) [W]
output RealOutput	QCoo_flow	Total cooling heat flow rate transferred to the loads (<=0) [W]
output RealOutput	PHea	Power drawn by heating system [W]
output RealOutput	PCoo	Power drawn by cooling system [W]
output RealOutput	PFan	Power drawn by fan motors [W]
output RealOutput	PPum	Power drawn by pump motors [W]
output RealOutput	QFue_flow[nFue]	Fuel energy input rate [W]
input RealInput	TDisRetSet	Setpoint for the maximum district return temperature [K]

Modelica definition

model BuildingTimeSeriesWithETS "Model of a building with loads provided as time series, connected to an ETS for heating" extends BaseClasses.PartialBuildingWithETS( redeclare Buildings.DHC.Loads.BaseClasses.BuildingTimeSeries bui( final have_heaWat=true, final have_chiWat=false, final have_hotWat=false, final filNam=filNam, T_aHeaWat_nominal=THeaWatSup_nominal, T_bHeaWat_nominal=THeaWatRet_nominal), mBui_flow_nominal=QHea_flow_nominal/(cp*dT_nominal), ets( QHeaWat_flow_nominal=QHea_flow_nominal)); final parameter Modelica.Units.SI.HeatFlowRate QHea_flow_nominal= bui.facMul * bui.QHea_flow_nominal "Space heating design load (>=0)"; parameter Modelica.Units.SI.TemperatureDifference dT_nominal(min=0)=10 "Water temperature drop/increase accross load and source-side HX (always positive)"; parameter Modelica.Units.SI.Temperature THeaWatSup_nominal=50 + 273.15 "Heating water supply temperature"; final parameter Modelica.Units.SI.Temperature THeaWatRet_nominal= THeaWatSup_nominal - dT_nominal "Heating water return temperature"; parameter Modelica.Fluid.Types.Dynamics energyDynamics=Modelica.Fluid.Types.Dynamics.SteadyState "Type of energy balance"; parameter Boolean use_inputFilter=false "= true, if pump speed is filtered with a 2nd order CriticalDamping filter"; parameter String filNam "Library path of the file with thermal loads as time series"; protected parameter Modelica.Units.SI.SpecificHeatCapacity cp=MediumSer.specificHeatCapacityCp( MediumSer.setState_pTX( MediumSer.p_default, MediumSer.T_default, MediumSer.X_default)) "Default specific heat capacity of medium"; end BuildingTimeSeriesWithETS;