.IBPSA.BoundaryConditions.SolarIrradiation.BaseClasses.SkyClearness

Information

This component computes the sky clearness.

Implementation

In the IBPSA library, HGloHor is always larger than 1E-4, minus some small undershoot due to regularization. Hence, the implementation is not simplified for HGloHor < Modelica.Constants.small.

The function call IBPSA.Utilities.Math.Functions.smoothMax is such that the regularization is usually not triggered.

Revisions

• September 23, 2016, by Michael Wetter:
  Changed deltaX from 0.1 to 0.01, and also optimized the code.
  This is for issue 521.
• May 5, 2015, by Michael Wetter:
  Introduced constant k to reduce number of operations.
• May 5, 2015, by Filip Jorissen:
  Converted algorithm section into equation section for easier differentiability.
• July 07, 2010, by Wangda Zuo:
  First implementation.