In real world there are plenty of cases where zones are nonconvex polygons.
It is a well known issue that energyplus cannot handle this, and it's up to the engineers designing simulation to do an alternative.
One of the best alternatives to circumvent this shortcoming is for example to split the zone into two or more convex zones, using as a separator a thin wall of air that lets all/almost all heat exchanges to occur between zones.
Following https://unmethours.com/question/13094/change-all-interior-walls-to-air-walls/ of course Honestly, it's knowledgeable that EnergyPlus is a complex simulation engine and documenting such into a couple of PDFs is no easy task, although there isn't easy information to be found regarding the issue of air walls, and have used this topic to check them out so, thanks.
Only question i have is about these materials you are using in Open Studio:
Material,
Air Wall Material, !- Name
MediumSmooth, !- Roughness
0.01, !- Thickness {m}
0.6, !- Conductivity {W/m-K}
800, !- Density {kg/m3}
1000, !- Specific Heat {J/kg-K}
0.95, !- Thermal Absorptance
0.7, !- Solar Absorptance
0.7; !- Visible Absorptance
So the basic idea here is using this Air Interior Wall surfaces to split non-convex L buildings/zones, or polygons with holes (aka interior rings) that create nonconvex shapes.
How? Adding an extra interior wall to L corners (this is done using computational geometry) and or ring corners, and then assigning them air wall material for the zone interface surfaces (one for each contiguous zone).
The issue with this material which would be supposed to mimick somehow the properties of airflow that seem not matching and if you can explain would be welcome are the following properties:
Roughness: shouldn't it be smooth (it's the most possible resembling to air layer or surface)
Thickness: shouldn't it be minimal (in documentation they do not recommend lower than 0,003 so 0,001 for example)
Solar and Visible absorptance shouldnt it be lower to match the material properties accordingly.
So thanks
EDIT (10/03/2020):
In a response to a question in advance.comments, due to its potential interest in more people checking this topic here is added further information.
Convex zone zone having a floor polygon projection (footprint) where each vertex connects to all others through a line that is always inside the polygon (i use this definition because i work with computational geometry and actually this is one way to compute if it is convex with algorithms, there are other definitions, like for example all external angles must be above 180º)
Non-Convex Zone opposite of convex (an L-Shape is one of the most common building non convex zones).
Why does this matter?
EnergyPlus engine part that treats beam solar radiation and reflectances from exterior surfaces that strike the building and, ultimately, enter the zone is not prepared to handle non-convex geometries because in these cases it would require further interactions that where not considered, specifically due to Interior. This engine part is defined in Building Class, and is the Field: Solar Distribution parameter of the Building class.
In practice Field:Solar distribution can have the values: MinimalShadowing, FullExterior, FullExteriorWithReflections, FullinteriorAndExterior, FullInteriorAndExteriorWithReflections.
for all of these if the building has a nonconvex zone it is recommended to choose replace the Interior options with other.
Will it affect much the model?
Usually not although in practice what is happening when using Interior: "instead of assuming all transmitted beam solar falls on the floor the program calculates the amount of beam radiation falling on each surface in the
zone, including floor, walls and windows, by projecting the sun’s rays through the exterior windows,
taking into account the effect of exterior shadowing surfaces and window shading devices." of course this how it is computed and in any case you can use and get values if you have a specific necessary, also for more information check EnergyPlus Input Output Reference chapter 1.4.4.1.7 of the 1.4.4 Building class.
Cheers.
