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Calculation method for solar fractions in HOM

Created by: FWuellhorst

What is the problem?

In order to validate the HOM, we need a intuitiv and phyiscal modelling of the short wave solar radiation entering through a window.

How do we want to solve it? Describe the solution you'd like

We need to identify how we can use solar fractions and shape factors to calculate which wall receives a certain percentage of the radiation through a window. Main goals are:

  • All calculations should be based on sources
  • The parametrization needs to be intuitiv
  • The results should be close to the results provided in the ASHRAE Standard

Related sources

Problems with the current implementation

Heres the list of all problems i identified during the process:

  • Different approaches for multiple windows. In ASHRAE140.EastWestFacingWindows, a MultiSum is used, in ASHRAE140.SouthFacingWindows, no sum is used, as only one window is present. I would propose a central approach.
  • A RealInput is used for the short waved radiation. The 'Buildings' library for example has it's own port.
  • Solar distribution factors are inside of each wall. However, the factors are calulated in the room they are applied in.