Annex60.BoundaryConditions.SolarGeometry.BaseClasses.Declination

# .Annex60.BoundaryConditions.SolarGeometry.BaseClasses.Declination

Declination angle

## 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 Annex60.BoundaryConditions.SolarGeometry.BaseClasses.Examples.Declination.

## Revisions

- 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.

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