functionSunDeclination
Information
Function computing the Sun's declination depending on (t0 + t) given in seconds
Hypothesis and equations
The function return the Sun's declination in radians given by the following equation:
delta:=(0.302 - 22.93*cos(wd) - 0.229*cos(2*wd) - 0.243*cos(3*wd) + 3.851*sin(wd) + 0.002*sin(2*wd) - 0.055*sin(3*wd))*pi/180
Where wd=2*pi/365<.25 * d (d day of the year according to t0+t)
The year is supposed to be not bisextile.
Bibliography
H. BOUIA, "Amélioration du temps de calcul dans BuildSysPro par traitements numériques optimisés de la conduction et des calculs solaires", Note H-E14-2013-00715-FR, 03/2013.
Instructions for use
none
Known limits / Use precautions
none
Validations
Validated function - Hassan BOUIA 03/2013.
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Licensed by EDF under a 3-clause BSD-license
Copyright © EDF 2009 - 2023
BuildSysPro version 3.6.0
Author : Hassan BOUIA, EDF (2013)
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Inputs
| Type | Name | Default | Description |
|---|---|---|---|
| Real | t0 | 0 | Time in seconds at t=0 |
| Modelica.Units.SI.Time | t | Time in seconds |
Outputs
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.Angle | delta | Sun's declination (angle in radians) |
Revisions
Hassan Bouia 03/2013 : Simplification de l'écriture et adaptation au nouveau modèle MeteoFile