This package provides component models for the infrared radiative heat exchange of window assemblies. The models are according to TARCOG 2006, except for the outdoor radiosity, which is computed by Buildings.HeatTransfer.Radiosity.OutdoorRadiosity. The outdoor radiosity is different from the TARCOG implementation so that the same equations are used for windows as are used for opaque walls in the room heat transfer model of the package Buildings.Rooms.
TARCOG 2006: Carli, Inc., TARCOG: Mathematical models for calculation of thermal performance of glazing systems with our without shading devices, Technical Report, Oct. 17, 2006.
Extends from Modelica.Icons.VariantsPackage (Icon for package containing variants).
Name | Description |
---|---|
Constant | Generate constant radiosity signal |
OpaqueSurface | Model for an opaque surface |
IndoorRadiosity | Model for indoor radiosity |
OutdoorRadiosity | Model for the outdoor radiosity that strikes the window |
RadiositySplitter | Splits the incoming radiosity into two flows based on an input signal |
Examples | Collection of models that illustrate model use and test models |
BaseClasses | Package with base classes for Buildings.HeatTransfer.Radiosity |
Constant radiosity source. This model requires k ≤ 0 because the radiosity leaves the component and hence needs to be negative or zero.
This model is used in Buildings.HeatTransfer.BaseClasses.DummyConstructionExterior.
Extends from Modelica.Blocks.Interfaces.BlockIcon (Basic graphical layout of input/output block).
Type | Name | Default | Description |
---|---|---|---|
Real | k | Radiosity that leaves this component (k <= 0) |
Type | Name | Description |
---|---|---|
output RadiosityOutflow | JOut | [W] |
block Constant "Generate constant radiosity signal" parameter Real k(max=0, start=0) "Radiosity that leaves this component (k <= 0)"; extends Modelica.Blocks.Interfaces.BlockIcon;Interfaces.RadiosityOutflow JOut; equation JOut = k;end Constant;
Extends from Buildings.HeatTransfer.Radiosity.BaseClasses.RadiosityOneSurface (Model for the radiosity balance of a device with one surface), Buildings.HeatTransfer.Radiosity.BaseClasses.ParametersOneSurface (Parameters that are used to model one surface).
Type | Name | Default | Description |
---|---|---|---|
Area | A | Surface area [m2] | |
Emissivity | absIR | Infrared absorptivity [1] | |
ReflectionCoefficient | rhoIR | 1 - absIR | Infrared reflectivity [1] |
TransmissionCoefficient | tauIR | 1 - rhoIR - absIR | Infrared transmissivity [1] |
Boolean | linearize | false | Set to true to linearize emissive power |
Temperature | T0 | 293.15 | Temperature used to linearize radiative heat transfer [K] |
Type | Name | Description |
---|---|---|
input RadiosityInflow | JIn | Incoming radiosity [W] |
output RadiosityOutflow | JOut | Outgoing radiosity [W] |
HeatPort_a | heatPort | Heat port of this surface |
model OpaqueSurface "Model for an opaque surface" extends Buildings.HeatTransfer.Radiosity.BaseClasses.RadiosityOneSurface; extends Buildings.HeatTransfer.Radiosity.BaseClasses.ParametersOneSurface( final tauIR=1 - rhoIR - absIR, final rhoIR=1 - absIR);Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a heatPort "Heat port of this surface"; protected final parameter Real T03( min=0, unit="K3") = T0^3 "3rd power of temperature T0"; final parameter Real T04( min=0, unit="K4") = T0^4 "4th power of temperature T0"; Real T4( min=1E8, start=293.15^4, nominal=1E10, unit="K4") "4th power of temperature"; equation T4 = if linearize then 4*T03*heatPort.T - 3*T04 else heatPort.T^4; 0 = JOut + A*absIR*Modelica.Constants.sigma*T4 + rhoIR*JIn; 0 = heatPort.Q_flow + JIn + JOut;end OpaqueSurface;
TARCOG 2006: Carli, Inc., TARCOG: Mathematical models for calculation of thermal performance of glazing systems with our without shading devices, Technical Report, Oct. 17, 2006.
Extends from Buildings.HeatTransfer.Radiosity.BaseClasses.RadiosityOneSurface (Model for the radiosity balance of a device with one surface), Buildings.HeatTransfer.Radiosity.BaseClasses.ParametersOneSurface (Parameters that are used to model one surface).
Type | Name | Default | Description |
---|---|---|---|
Area | A | Surface area [m2] | |
Emissivity | absIR | 1 | Infrared absorptivity [1] |
ReflectionCoefficient | rhoIR | 0 | Infrared reflectivity [1] |
TransmissionCoefficient | tauIR | 0 | Infrared transmissivity [1] |
Boolean | linearize | false | Set to true to linearize emissive power |
Temperature | T0 | 293.15 | Temperature used to linearize radiative heat transfer [K] |
Type | Name | Description |
---|---|---|
input RadiosityInflow | JIn | Incoming radiosity [W] |
output RadiosityOutflow | JOut | Outgoing radiosity [W] |
HeatPort_a | heatPort | Heat port of this surface |
model IndoorRadiosity "Model for indoor radiosity" extends Buildings.HeatTransfer.Radiosity.BaseClasses.RadiosityOneSurface; extends Buildings.HeatTransfer.Radiosity.BaseClasses.ParametersOneSurface( final absIR=1, final tauIR=0, final rhoIR=0);Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a heatPort "Heat port of this surface"; protected final parameter Real T03( min=0, unit="K3") = T0^3 "3rd power of temperature T0"; final parameter Real T04( min=0, unit="K4") = T0^4 "4th power of temperature T0"; Real T4( min=1E8, start=293.15^4, nominal=1E10, unit="K4") "4th power of temperature"; equation T4 = if linearize then 4*T03*heatPort.T - 3*T04 else heatPort.T^4; JOut = -A*Modelica.Constants.sigma*T4; 0 = heatPort.Q_flow + JIn + JOut;end IndoorRadiosity;
Model for the infrared radiosity balance of the outdoor environment.
Type | Name | Default | Description |
---|---|---|---|
Area | A | Area of receiving surface [m2] | |
Real | vieFacSky | View factor from receiving surface to sky (=1 for roofs) | |
Boolean | linearize | false | Set to true to linearize emissive power |
Temperature | T0 | 293.15 | Temperature used to linearize radiative heat transfer [K] |
Type | Name | Description |
---|---|---|
input RealInput | TOut | Outside temperature [K] |
input RealInput | TBlaSky | Black body sky temperature [K] |
output RadiosityOutflow | JOut | Radiosity that flows out of component [W] |
model OutdoorRadiosity "Model for the outdoor radiosity that strikes the window" parameter Modelica.SIunits.Area A "Area of receiving surface"; parameter Real vieFacSky(min=0, max=1) "View factor from receiving surface to sky (=1 for roofs)"; parameter Boolean linearize=false "Set to true to linearize emissive power"; parameter Modelica.SIunits.Temperature T0=293.15 "Temperature used to linearize radiative heat transfer"; Real TRad4(unit="K4") "4th power of the mean outdoor temperature"; Modelica.SIunits.Temperature TRad "Mean radiant temperature";Modelica.Blocks.Interfaces.RealInput TOut( final quantity="ThermodynamicTemperature", final unit="K", min=0) "Outside temperature"; Modelica.Blocks.Interfaces.RealInput TBlaSky( final quantity="ThermodynamicTemperature", final unit="K", min=0) "Black body sky temperature"; Buildings.HeatTransfer.Interfaces.RadiosityOutflow JOut "Radiosity that flows out of component"; protected final parameter Real T03( min=0, unit="K3") = T0^3 "3rd power of temperature T0"; final parameter Real T04( min=0, unit="K4") = T0^4 "4th power of temperature T0"; equation TRad4 = (vieFacSky*TBlaSky^4 + (1 - vieFacSky)*TOut^4); JOut = -A*Modelica.Constants.sigma*TRad4; TRad = if linearize then (TRad4 + 3*T04)/(4*T03) else TRad4^(1/4);end OutdoorRadiosity;
This blocks splits the incoming radiosity into two fluxes according to
JOut,1 = - u JIn,
JOut,2 = - (1-u) JIn.
This block may be used to split the radiosity flux into a fraction that strikes the shaded part of a window, and a fraction that strikes the non-shaded part.
Extends from Modelica.Blocks.Interfaces.BlockIcon (Basic graphical layout of input/output block).
Type | Name | Description |
---|---|---|
input RadiosityInflow | JIn | [W] |
input RealInput | u | u times incoming radiosity |
output RadiosityOutflow | JOut_1 | [W] |
output RadiosityOutflow | JOut_2 | (1-u) times incoming radiosity [W] |
block RadiositySplitter "Splits the incoming radiosity into two flows based on an input signal" extends Modelica.Blocks.Interfaces.BlockIcon;Interfaces.RadiosityInflow JIn; Modelica.Blocks.Interfaces.RealInput u(min=0, max=1) "u times incoming radiosity"; Interfaces.RadiosityOutflow JOut_1; Interfaces.RadiosityOutflow JOut_2 "(1-u) times incoming radiosity"; equation JOut_1 = - u * JIn; JOut_2 = - (1-u)* JIn;end RadiositySplitter;