Solar Gains in Exterior Sliver Space are Large

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bbrannon4
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Solar Gains in Exterior Sliver Space are Large

Post by bbrannon4 »

I was testing some issues with heat building up near glazing and I noticed this odd behavior. This is a test model where I have a small sliver (0.1m) of space by the glass, with holes in all interior walls. The sliver is 2.27m2 and the room behind it is 81.72m2. Other than the interior wall connecting the two, there are no holes in the model connecting to other adjacencies (this is facing south in the southern hemisphere).

When I look at the solar gains for an example day, the sliver peaks at 1.7kW and the main room at 3.1kW. Since the sliver is so small and there is a 100% hole, I would expect basically all of the sunlight to pass through the sliver and land in the main room. Any explanation for why I'm wrong, or what might be going on?

Suncast was run and enabled.
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Complex Potential
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Re: Solar Gains in Exterior Sliver Space are Large

Post by Complex Potential »

Hi

I'm a little rusty on my apache engine knowledge but I think that solar gains are mostly driven by where the sunlight lands rather than what it passes through. In other words, sunlight only turns into solar gain in a room when it strikes a surface and heats that surface up. So it makes sense that the majority of the solar gain is seen in the room behind the sliver.

However, as you say, there is still a decent chuck experienced in the sliver. My guess would be that this is being driven by the glass surface. What you might expect to show up as conduction gain could be getting processed as solar gain within apache.

Hope this helps

CP
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