functionCalculAlphaTauDoubleGlazing
Information
Hypothesis and equations
This function calculates the absorption and transmission coefficients of a double glazing window, for direct and diffuse solar fluxes, from manufacturer data :
- Uw : Heat transfert coefficient of the window [W/m².K]
- g : Solar factor of the glazing [between 0 and 1]
- tau0 : Coefficient of energy transmission of the glazing [between 0 and 1]
Bibliography
Standard EN 410 for calculation of equivalent coefficients for direct solar flux on normal incidence.
Method Th-S from RT for calculation of equivalent coefficients for diffuse solar flux.
Instructions for use
none
Known limits / Use precautions
none
Validations
Validated model - Benoît Charrier 02/2016
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Licensed by EDF under a 3-clause BSD-license
Copyright © EDF 2009 - 2023
BuildSysPro version 3.6.0
Author : Benoît CHARRIER, EDF (2016)
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Inputs
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.CoefficientOfHeatTransfer | Uw | Heat transfert coefficient of the window | |
| Real | g | Solar factor of the window [between 0 and 1] | |
| Real | tau0 | Coefficient of energy transmission [between 0 and 1] | |
| Modelica.Units.SI.CoefficientOfHeatTransfer | Hext | 21 | Global surface exchange coefficient on the outer face of the window |
| Modelica.Units.SI.CoefficientOfHeatTransfer | Hint | 8.29 | Global surface exchange coefficient on the inner face of the window |
Outputs
| Type | Name | Default | Description |
|---|---|---|---|
| Real | alpha_dir | Direct absorption coefficient of the window | |
| Real | alpha_dif | Diffuse absorption coefficient of the window | |
| Real | tau_dir | Direct transmission coefficient of the window | |
| Real | tau_dif | Diffuse transmission coefficient of the window |
Revisions
Benoît Charrier 08/2017 : correction of errors in documentation and parameter naming, manufacturer data needed are the coefficient of energy transmission of the glazing (tau0) and the solar factor of the glazing (g).