blockDeclination
Declination angle
Extends from Buildings.BoundaryConditions.WeatherData.BaseClasses.PartialConvertTime.
Information
This component computes the solar declination, which is
the angle between the equatorial plane and the solar beam.
The input signal nDay is the one-based number of the day, but in seconds.
Hence, during January 1, we should have nDay = 86400 seconds.
Since the effect of using a continuous number rather than an integer is small,
we approximate this so that nDay = 0 at the start of January 1,
and nDay = 86400 at the end of January 1.
Validation
A validation with a more detailed calculation can be found at Buildings.BoundaryConditions.SolarGeometry.BaseClasses.Examples.Declination.
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Blocks.Interfaces.RealInput | nDay | Day number with units of seconds | |
| Modelica.Blocks.Interfaces.RealOutput | decAng | Solar declination angle |
Revisions
-
March 27, 2023, by Ettore Zanetti:
Updated to use partial class for conversion from simulation time to calendar time.
This is for IBPSA #1716. -
January 6, 2015, by Michael Wetter:
Updated documentation and added validation. This is for issue 382. -
January 5, 2015, by Michael Wetter:
Updated comment of output signal as this is used in the weather bus connector. This is for issue 376. -
November 11, 2015, by Michael Wetter:
Corrected typo in documentation. -
Dec 7, 2010, by Michael Wetter:
Rewrote equation in explicit form to avoid nonlinear equations in room model. -
May 17, 2010, by Wangda Zuo:
First implementation.