When we export internal mass object we should double the area (Bugzilla #868)

[axelstudios]

On 2012-08-28 13:27:51, @DavidGoldwasser wrote:

While it would seem like you end up with double the mass but right area, it seems EnergyPlus may address this internally. I confirmed with Brent that this is the correct approach.

This is in reference to a forum post (see URL)

Keywords: BadSimResults, ForwardTranslation

[DavidGoldwasser]

After unmet hours post looking back at this https://unmethours.com/question/10810/openstudio-merged-surfaces-inside-a-thermal-zone-to-internalmass/

Here is feedback from Edwin.

Cut the wall in half and unfold it. Like the attached image. You'll need to cut the wall in half. For convenience, I'd suggest just creating material layers of 1/2 thickness from the original partition and create a new 1/2 thickness partition construction to use as the internal mass construction. The surface area will be twice the original so that the same area is exposed to the air as before. I can come up with a more rigorous analysis of this if needed, but that should suffice for now.

[DavidGoldwasser]

Issue #687 is related to this. It also addresses the concept of merging internal mass with a zone that use the same construction to speed up simulation, but there are some limitations.

[DavidGoldwasser]

May also think about what we are doing for interior partitions. I believe we export 1ft^2 for 1ft^2. Of course in this case the use has more control to do what they want. By default interior partitions don't convert to internal mass. I expect not many people are flipping that switch.