Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
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.
| | 2 | No.2 Revision |
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.
