.Buildings.HeatTransfer.Data.Glasses

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.

• the surface a is usually the outside-facing surface, and the surface b is usually the room-facing surface.
• by the term solar, we mean the whole solar spectrum. Data in the solar spectrum are used for computing solar heat gains.
• by the term infrared (or infrared), we mean the infrared spectrum. Data in the infrared spectrum are used for thermal radiation that is emitted by surfaces that are around room or ambient temperature.
• WINDOW 6 uses spectral data in the calculation of optical properties of window systems, whereas the model in this library uses averages over the whole solar or infrared spectrum.

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.ThermalZones.Detailed.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.

Contents

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

Revisions

• September 9, 2010, by Michael Wetter:
  First implementation.