A partial selection of concepts to consider. Based on your description, I'm assuming that there is a modelled pair of adjacent interzone walls separating both zones. And that each interzone wall holds a conventional interzone window, i.e. no Construction:AirBoundary objects involved. Given that, I'm simply drawing your attention to the following specific points of discussion in the Engineering Reference:
Solar Distribution, in particular the options FullInteriorAndExterior and FulInteriorAndlExteriorWithReflections. This is set in the IDF using the Building object. These options come with a price with regards to zone geometry (enclosed, convex), yet ensure that some of the transmitted beam solar radiation may make its way to the adjacent zone (through the interzone window). An excerpt:
If you use FullInteriorAndExterior the
program will calculate how much beam
radiation falling on an interior
window is absorbed by the window, how
much is reflected back into the zone,
and how much is transmitted into the
adjacent zone.
Details of the Interior Solar Distribution Calculation, quoting:
EnergyPlus calculates the distribution
of short-wave radiation in the
interior of each thermal zone. This
radiation consists of beam solar
radiation, diffuse solar
radiation, and short-wave radiation
from electric lights. The program
determines the amount of this
radiation that is (1) absorbed on the
inside face of opaque surfaces, (2)
absorbed in the glass and shading
device layers of the zone’s exterior
and interior windows, (3)
transmitted through the zone’s
interior windows to adjacent zones, and (4) transmitted back out
of the exterior windows.
Interior Diffuse Radiation, again quoting (towards the end):
[...] taking into account multiple
reflection between zones. For example,
for two zones means that some of the
radiation transmitted from Zone1 to
Zone2 is reflected back to Zone1, and
some of this is in turn reflected back
to Zone2, etc.
Interior Solar Radiation Transmitted by Interior Windows, notably the different treatment of beam vs diffuse:
The program does not track where this
radiation falls in the adjacent
zone: it is counted as diffuse
radiation in that zone.
Hope these excerpts help you.
EDIT: In a nutshell, as long as you're selecting either FullInteriorAndExterior or FulInteriorAndlExteriorWithReflections as the Building's Solar Distribution option, and that zone geometry is enclosed & convex, you'll get just about what you're looking for.
Which application? EnergyPlus?
Hi Denis, sorry I should have mentioned earlier. Yes I am working on EnergyPlus.