Shading surfaces and radiation in EnergyPlus

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Hello together,

I am wondering how the shadow calculation in EnergyPlus exactly works. In detail, I would like to know which radiation components are taken into account in my simulation and which are not. I have a thermal zone that is shaded by a few detached shading objects, which are neighboring buildings.

Regarding radiation, I would differentiate between 1. direct solar radiation, 2. diffuse solar radiation, and 3. long-wave radiation (influencing the energy balance of the surfaces of my thermal zone). What I understood so far:

1.shading of direct solar radiation (sky)

• is taken into account geometrically

2.shading of diffuse solar radiation (sky, ground)

• only considered regarding the sky --> calculation of a modifier for the sky view factor

• not considered for the ground(?)

3.shading of long-wave radiation:

• coming from the sky --> yes, via an isotropic shading factor R_dome

• coming from the ground --> no blocking

• "The long-wave radiation from these obstructions is added to the long-wave radiation from the ground; in this calculation both obstructions and ground are assumed to be at the outside air temperature and to have an emissivity of 0.9." (EnergyPlus Engineering Reference)

4.what shading surfaces "(not) do":

• using Full(InteriorAnd)ExteriorWithReflections in the Building object --> shading surfaces also reflect solar radiation onto the building, AND they shade diffuse solar radiation coming from the ground, not only from the sky (EnergyPlus Input Output Reference) (shading/blocking of long-wave radiation from the ground is still not considered?)

• do shading objects emit and reflect long-wave radiation?

Is that correct? My questions are written in italics.

I appreciate any help!

Best, M.