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Buildings.HeatTransfer.Data.Glasses

Package with thermophysical properties for window glas

Information

This package implements thermophysical properties for window glass.

Since the infrared transmissivity is part of the Window 6 data and since it depends on the glass thickness, the glass thickness is a parameter that is set for all glass layers. This configuration is different from the records for gas properties, which do not yet set the value for the thickness of the gas gap.

The table below compares the data of this record with the variables used in the WINDOW 6 output file.

Note that
Buildings library variable name WINDOW 6 variable name
tauSol Tsol
rhoSol_a Rsol1
rhoSol_b Rsol2
tauIR Tir
absIR_a Emis1
absIR_b Emis2

The solar transmittance tauSol and the solar reflectances rhoSol_a and rhoSol_b are vectors. For regular glass, these vectors have only one element. For electrochromic glass, users can enter an arbitrary number of elements, where each element is for a particular window state. The dimension of the three vectors tauSol, rhoSol_a and rhoSol_b must be equal.

The example Buildings.Rooms.Examples.ElectroChromicWindow shows how these data can be used to darken the window. A control signal of uWin=0 in the room model corresponds to the first entry of the data, which typically is the clear state, whereas uWin=1 corresponds to the last entry, which typically is the dark states. For intermediate control signals, the optical properties are interpolated using the model Buildings.HeatTransfer.Windows.BaseClasses.StateInterpolator.

Extends from Modelica.Icons.MaterialPropertiesPackage (Icon for package containing property classes).

Package Content

Name Description
Buildings.HeatTransfer.Data.Glasses.Generic Generic Thermal properties of window glass
Buildings.HeatTransfer.Data.Glasses.ID100 ID100 Generic Bronze Glass 3.1mm. Manufacturer: Generic.
Buildings.HeatTransfer.Data.Glasses.ID101 ID101 Generic Bronze Glass 5.7mm. Manufacturer: Generic.
Buildings.HeatTransfer.Data.Glasses.ID102 ID102 Generic Clear Glass 3.048mm. Manufacturer: Generic.
Buildings.HeatTransfer.Data.Glasses.ID103 ID103 Generic Clear Glass 5.7mm. Manufacturer: Generic.
Buildings.HeatTransfer.Data.Glasses.Electrochromic Electrochromic Electrochromic Glass 6mm. Manufacturer: Generic.

Buildings.HeatTransfer.Data.Glasses.Generic Buildings.HeatTransfer.Data.Glasses.Generic

Thermal properties of window glass

Information

This record implements thermophysical properties for window glass. See Buildings.HeatTransfer.Data.Glasses for instructions.

Extends from Modelica.Icons.Record (Icon for records).

Parameters

TypeNameDefaultDescription
Lengthx0.003Thickness [m]
ThermalConductivityk1Thermal conductivity [W/(m.K)]
TransmissionCoefficienttauSol[:]{0.6}Solar transmittance [1]
ReflectionCoefficientrhoSol_a[:]{0.075}Solar reflectance of surface a (usually outside-facing surface) [1]
ReflectionCoefficientrhoSol_b[:]{0.075}Solar reflectance of surface b (usually room-facing surface) [1]
TransmissionCoefficienttauIR0Infrared transmissivity of glass [1]
EmissivityabsIR_a0.84Infrared absorptivity of surface a (usually outside-facing surface) [1]
EmissivityabsIR_b0.84Infrared absorptivity of surface b (usually room-facing surface) [1]

Modelica definition

record Generic "Thermal properties of window glass" extends Modelica.Icons.Record; parameter Modelica.SIunits.Length x=0.003 "Thickness"; parameter Modelica.SIunits.ThermalConductivity k=1 "Thermal conductivity"; parameter Modelica.SIunits.TransmissionCoefficient tauSol[:] = {0.6} "Solar transmittance"; parameter Modelica.SIunits.ReflectionCoefficient rhoSol_a[:] = {0.075} "Solar reflectance of surface a (usually outside-facing surface)"; parameter Modelica.SIunits.ReflectionCoefficient rhoSol_b[:] = {0.075} "Solar reflectance of surface b (usually room-facing surface)"; parameter Modelica.SIunits.TransmissionCoefficient tauIR = 0 "Infrared transmissivity of glass"; parameter Modelica.SIunits.Emissivity absIR_a = 0.84 "Infrared absorptivity of surface a (usually outside-facing surface)"; parameter Modelica.SIunits.Emissivity absIR_b = 0.84 "Infrared absorptivity of surface b (usually room-facing surface)"; end Generic;

Buildings.HeatTransfer.Data.Glasses.ID100 Buildings.HeatTransfer.Data.Glasses.ID100

Generic Bronze Glass 3.1mm. Manufacturer: Generic.

Parameters

TypeNameDefaultDescription
Lengthx0.0031Thickness [m]
ThermalConductivityk1.0Thermal conductivity [W/(m.K)]
TransmissionCoefficienttauSol[:]{0.646}Solar transmittance [1]
ReflectionCoefficientrhoSol_a[:]{0.062}Solar reflectance of surface a (usually outside-facing surface) [1]
ReflectionCoefficientrhoSol_b[:]{0.063}Solar reflectance of surface b (usually room-facing surface) [1]
TransmissionCoefficienttauIR0Infrared transmissivity of glass [1]
EmissivityabsIR_a0.84Infrared absorptivity of surface a (usually outside-facing surface) [1]
EmissivityabsIR_b0.84Infrared absorptivity of surface b (usually room-facing surface) [1]

Modelica definition

record ID100 = Buildings.HeatTransfer.Data.Glasses.Generic ( x=0.0031, k=1.0, tauSol={0.646}, rhoSol_a={0.062}, rhoSol_b={0.063}, tauIR=0, absIR_a=0.84, absIR_b=0.84) "Generic Bronze Glass 3.1mm. Manufacturer: Generic.";

Buildings.HeatTransfer.Data.Glasses.ID101 Buildings.HeatTransfer.Data.Glasses.ID101

Generic Bronze Glass 5.7mm. Manufacturer: Generic.

Parameters

TypeNameDefaultDescription
Lengthx0.0057Thickness [m]
ThermalConductivityk1.0Thermal conductivity [W/(m.K)]
TransmissionCoefficienttauSol[:]{0.486}Solar transmittance [1]
ReflectionCoefficientrhoSol_a[:]{0.053}Solar reflectance of surface a (usually outside-facing surface) [1]
ReflectionCoefficientrhoSol_b[:]{0.053}Solar reflectance of surface b (usually room-facing surface) [1]
TransmissionCoefficienttauIR0Infrared transmissivity of glass [1]
EmissivityabsIR_a0.84Infrared absorptivity of surface a (usually outside-facing surface) [1]
EmissivityabsIR_b0.84Infrared absorptivity of surface b (usually room-facing surface) [1]

Modelica definition

record ID101 = Buildings.HeatTransfer.Data.Glasses.Generic ( x=0.0057, k=1.0, tauSol={0.486}, rhoSol_a={0.053}, rhoSol_b={0.053}, tauIR=0, absIR_a=0.84, absIR_b=0.84) "Generic Bronze Glass 5.7mm. Manufacturer: Generic.";

Buildings.HeatTransfer.Data.Glasses.ID102 Buildings.HeatTransfer.Data.Glasses.ID102

Generic Clear Glass 3.048mm. Manufacturer: Generic.

Parameters

TypeNameDefaultDescription
Lengthx0.003Thickness [m]
ThermalConductivityk1.0Thermal conductivity [W/(m.K)]
TransmissionCoefficienttauSol[:]{0.834}Solar transmittance [1]
ReflectionCoefficientrhoSol_a[:]{0.075}Solar reflectance of surface a (usually outside-facing surface) [1]
ReflectionCoefficientrhoSol_b[:]{0.075}Solar reflectance of surface b (usually room-facing surface) [1]
TransmissionCoefficienttauIR0Infrared transmissivity of glass [1]
EmissivityabsIR_a0.84Infrared absorptivity of surface a (usually outside-facing surface) [1]
EmissivityabsIR_b0.84Infrared absorptivity of surface b (usually room-facing surface) [1]

Modelica definition

record ID102 = Buildings.HeatTransfer.Data.Glasses.Generic ( x=0.003, k=1.0, tauSol={0.834}, rhoSol_a={0.075}, rhoSol_b={0.075}, tauIR=0, absIR_a=0.84, absIR_b=0.84) "Generic Clear Glass 3.048mm. Manufacturer: Generic.";

Buildings.HeatTransfer.Data.Glasses.ID103 Buildings.HeatTransfer.Data.Glasses.ID103

Generic Clear Glass 5.7mm. Manufacturer: Generic.

Parameters

TypeNameDefaultDescription
Lengthx0.0057Thickness [m]
ThermalConductivityk1.0Thermal conductivity [W/(m.K)]
TransmissionCoefficienttauSol[:]{0.771}Solar transmittance [1]
ReflectionCoefficientrhoSol_a[:]{0.070}Solar reflectance of surface a (usually outside-facing surface) [1]
ReflectionCoefficientrhoSol_b[:]{0.070}Solar reflectance of surface b (usually room-facing surface) [1]
TransmissionCoefficienttauIR0Infrared transmissivity of glass [1]
EmissivityabsIR_a0.84Infrared absorptivity of surface a (usually outside-facing surface) [1]
EmissivityabsIR_b0.84Infrared absorptivity of surface b (usually room-facing surface) [1]

Modelica definition

record ID103 = Buildings.HeatTransfer.Data.Glasses.Generic ( x=0.0057, k=1.0, tauSol={0.771}, rhoSol_a={0.070}, rhoSol_b={0.070}, tauIR=0, absIR_a=0.84, absIR_b=0.84) "Generic Clear Glass 5.7mm. Manufacturer: Generic.";

Buildings.HeatTransfer.Data.Glasses.Electrochromic Buildings.HeatTransfer.Data.Glasses.Electrochromic

Electrochromic Glass 6mm. Manufacturer: Generic.

Parameters

TypeNameDefaultDescription
Lengthx0.006Thickness [m]
ThermalConductivityk0.9Thermal conductivity [W/(m.K)]
TransmissionCoefficienttauSol[:]{0.814,0.111}Solar transmittance [1]
ReflectionCoefficientrhoSol_a[:]{0.086,0.179}Solar reflectance of surface a (usually outside-facing surface) [1]
ReflectionCoefficientrhoSol_b[:]{0.086,0.179}Solar reflectance of surface b (usually room-facing surface) [1]
TransmissionCoefficienttauIR0Infrared transmissivity of glass [1]
EmissivityabsIR_a0.84Infrared absorptivity of surface a (usually outside-facing surface) [1]
EmissivityabsIR_b0.84Infrared absorptivity of surface b (usually room-facing surface) [1]

Modelica definition

record Electrochromic = Buildings.HeatTransfer.Data.Glasses.Generic ( x=0.006, k=0.9, tauSol={0.814, 0.111}, rhoSol_a={0.086, 0.179}, rhoSol_b={0.086, 0.179}, tauIR=0, absIR_a=0.84, absIR_b=0.84) "Electrochromic Glass 6mm. Manufacturer: Generic.";

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