modelThreeElements

Thermal Zone with three elements for exterior walls, interior walls and floor plate

Extends from TwoElements (Thermal Zone with two elements for exterior and interior walls).

Information

This model adds one further element for the floor plate. Long-term effects dominate the excitation of the floor plate and thus the excitation fundamentally differs from excitation of outer walls. Adding an extra element for the floor plate leads to a finer resolution of the dynamic behaviour but increases calculation times. The floor plate is parameterized via the length of the RC-chain nFloor, the vector of the capacities CFloor[nFloor], the vector of the resistances RFloor[nFloor] and the remaining resistance RFloorRem.

The image below shows the RC-network of this model.

Parameters

Type	Name	Default	Description
Boolean	use_moisture_balance (from OneElement)	false	If true, input connector QLat_flow is enabled and room air computes moisture balance
Dynamics › Conservation equations
Modelica.Fluid.Types.Dynamics	energyDynamics (from LumpedVolumeDeclarations)	Modelica.Fluid.Types.Dynamics.DynamicFreeInitial	Type of energy balance: dynamic (3 initialization options) or steady state
Modelica.Fluid.Types.Dynamics	substanceDynamics (from LumpedVolumeDeclarations)	energyDynamics	Type of independent mass fraction balance: dynamic (3 initialization options) or steady state
Modelica.Fluid.Types.Dynamics	traceDynamics (from LumpedVolumeDeclarations)	energyDynamics	Type of trace substance balance: dynamic (3 initialization options) or steady state
Advanced › Dynamics
Modelica.Fluid.Types.Dynamics	massDynamics (from LumpedVolumeDeclarations)	energyDynamics	Type of mass balance: dynamic (3 initialization options) or steady state, must be steady state if energyDynamics is steady state
Initialization
Medium.AbsolutePressure	p_start (from LumpedVolumeDeclarations)	Medium.p_default	Start value of pressure
Medium.Temperature	T_start (from LumpedVolumeDeclarations)	Medium.T_default	Start value of temperature
Medium.MassFraction[Medium.nX]	X_start (from LumpedVolumeDeclarations)	Medium.X_default	Start value of mass fractions m_i/m
Medium.ExtraProperty[Medium.nC]	C_start (from LumpedVolumeDeclarations)	fill(0, Medium.nC)	Start value of trace substances
Medium.ExtraProperty[Medium.nC]	C_nominal (from LumpedVolumeDeclarations)	fill(1E-2, Medium.nC)	Nominal value of trace substances. (Set to typical order of magnitude.)
Dynamics
Real	mSenFac (from LumpedVolumeDeclarations)	1	Factor for scaling the sensible thermal mass of the volume
Thermal zone
Modelica.Units.SI.Volume	VAir (from OneElement)		Air volume of the zone
Modelica.Units.SI.CoefficientOfHeatTransfer	hRad (from OneElement)		Coefficient of heat transfer for linearized radiation exchange between walls
Integer	nOrientations (from OneElement)		Number of orientations
General › Ports
Integer	nPorts (from OneElement)	0	Number of fluid ports
Windows
Modelica.Units.SI.Area[nOrientations]	AWin (from OneElement)		Vector of areas of windows by orientations
Modelica.Units.SI.Area[nOrientations]	ATransparent (from OneElement)		Vector of areas of transparent (solar radiation transmittend) elements by orientations
Modelica.Units.SI.CoefficientOfHeatTransfer	hConWin (from OneElement)		Convective coefficient of heat transfer of windows (indoor)
Modelica.Units.SI.ThermalResistance	RWin (from OneElement)		Resistor for windows
Modelica.Units.SI.TransmissionCoefficient	gWin (from OneElement)		Total energy transmittance of windows
Real	ratioWinConRad (from OneElement)		Ratio for windows between indoor convective and radiative heat emission
Boolean	indoorPortWin (from OneElement)	false	Additional heat port at indoor surface of windows
Exterior walls
Modelica.Units.SI.Area[nOrientations]	AExt (from OneElement)		Vector of areas of exterior walls by orientations
Modelica.Units.SI.CoefficientOfHeatTransfer	hConExt (from OneElement)		Convective coefficient of heat transfer of exterior walls (indoor)
Integer	nExt (from OneElement)		Number of RC-elements of exterior walls
Modelica.Units.SI.ThermalResistance[nExt]	RExt (from OneElement)		Vector of resistances of exterior walls, from inside to outside
Modelica.Units.SI.ThermalResistance	RExtRem (from OneElement)		Resistance of remaining resistor RExtRem between capacity n and outside
Modelica.Units.SI.HeatCapacity[nExt]	CExt (from OneElement)		Vector of heat capacities of exterior walls, from inside to outside
Boolean	indoorPortExtWalls (from OneElement)	false	Additional heat port at indoor surface of exterior walls
Advanced
Boolean	use_C_flow (from OneElement)	false	Set to true to enable input connector for trace substance
Interior walls
Modelica.Units.SI.Area	AInt (from TwoElements)		Area of interior walls
Modelica.Units.SI.CoefficientOfHeatTransfer	hConInt (from TwoElements)		Convective coefficient of heat transfer of interior walls (indoor)
Integer	nInt (from TwoElements)		Number of RC-elements of interior walls
Modelica.Units.SI.ThermalResistance[nInt]	RInt (from TwoElements)		Vector of resistances of interior walls, from port to center
Modelica.Units.SI.HeatCapacity[nInt]	CInt (from TwoElements)		Vector of heat capacities of interior walls, from port to center
Boolean	indoorPortIntWalls (from TwoElements)	false	Additional heat port at indoor surface of interior walls
Floor plate
Modelica.Units.SI.Area	AFloor		Area of floor plate
Modelica.Units.SI.CoefficientOfHeatTransfer	hConFloor		Convective coefficient of heat transfer of floor plate (indoor)
Integer	nFloor		Number of RC-elements of floor plate
Modelica.Units.SI.ThermalResistance[nFloor]	RFloor		Vector of resistances of floor plate, from inside to outside
Modelica.Units.SI.ThermalResistance	RFloorRem		Resistance of remaining resistor RFloorRem between capacity n and outside
Modelica.Units.SI.HeatCapacity[nFloor]	CFloor		Vector of heat capacities of floor plate, from inside to outside
Boolean	indoorPortFloor	false	Additional heat port at indoor surface of floor plate

Connectors

Type	Name	Description
Modelica.Blocks.Interfaces.RealInput[nOrientations]	solRad (from OneElement)	Solar radiation transmitted through windows
Modelica.Blocks.Interfaces.RealInput	QLat_flow (from OneElement)	Latent heat gains for the room
Modelica.Blocks.Interfaces.RealOutput	TAir (from OneElement)	Indoor air temperature
Modelica.Blocks.Interfaces.RealOutput	TRad (from OneElement)	Mean indoor radiation temperature
Modelica.Fluid.Vessels.BaseClasses.VesselFluidPorts_b[nPorts]	ports (from OneElement)	Auxiliary fluid inlets and outlets to indoor air volume
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a	extWall (from OneElement)	Ambient port for exterior walls
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a	window (from OneElement)	Ambient port for windows
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a	intGainsConv (from OneElement)	Auxiliary port for sensible internal convective gains
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a	intGainsRad (from OneElement)	Auxiliary port for internal radiative gains
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a	windowIndoorSurface (from OneElement)	Auxiliary port at indoor surface of windows
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a	extWallIndoorSurface (from OneElement)	Auxiliary port at indoor surface of exterior walls
Modelica.Blocks.Interfaces.RealInput	C_flow (from OneElement)	Trace substance mass flow rate added to the thermal zone
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a	intWallIndoorSurface (from TwoElements)	Auxiliary port at indoor surface of interior walls
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a	floor	Ambient port for floor plate
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a	floorIndoorSurface	Auxiliary port at indoor surface of floor plate

Components

Type	Name	Description
Fluid.MixingVolumes.MixingVolume	volAir (from OneElement)	Indoor air volume
Fluid.MixingVolumes.MixingVolumeMoistAir	volMoiAir (from OneElement)	Indoor air volume
Modelica.Thermal.HeatTransfer.Components.ThermalResistor	resWin (from OneElement)	Resistor for windows
Modelica.Thermal.HeatTransfer.Sources.PrescribedHeatFlow	convHeatSol (from OneElement)	Solar heat considered as convection
Modelica.Thermal.HeatTransfer.Sources.PrescribedHeatFlow[nOrientations]	radHeatSol (from OneElement)	Solar heat considered as radiation
BaseClasses.ThermSplitter	thermSplitterIntGains (from OneElement)	Splits incoming internal gains into separate gains for each wall element, weighted by their area
BaseClasses.ThermSplitter	thermSplitterSolRad (from OneElement)	Splits incoming solar radiation into separate gains for each wall element, weighted by their area
BaseClasses.ExteriorWall	extWallRC (from OneElement)	RC-element for exterior walls
BaseClasses.InteriorWall	intWallRC (from TwoElements)	RC-element for interior walls
BaseClasses.ExteriorWall	floorRC	RC-element for floor plate

Revisions

March 7, 2022, by Michael Wetter:
Removed massDynamics.
This is for #1542.
December 9, 2019, by Moritz Lauster:
Changes nExt to nFloor for RFloor and CFloor
July 11, 2019, by Katharina Brinkmann:
Renamed alphaFloor to hConFloor, alphaFloorConst to hConFloor_const
August 31, 2018 by Moritz Lauster:
Updated schema in documentation to fix issue 997.
July 15, 2015 by Moritz Lauster:
First Implementation.