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Long-wave radiation exchange between surfaces of 2 zones connected via airwall

asked 2022-01-20 07:33:18 -0500

Iason Bournas's avatar

updated 2022-12-02 09:29:42 -0500

Hi,

I have an E+ model that includes 2 thermal zones (Zone 1 and Zone 2) connected via an airwall (open air connection). I wanted to output for each surface of the model the longwave radiation (thermal) received from the rest of the surfaces (surfaces of both Zones 1 and 2). I found in the input/output reference a variable called "Surface Inside Face Net Surface Thermal Radiation Heat Gain Rate", which is described as "the heat transferred by longwave infrared thermal radiation exchanges between the inside faces of other surfaces in the zone". So I had 2 questions: Does that mean that for a surface X in Zone 1 this output variable does not consider the long-wave radiation emitted by surfaces of Zone 2? Can I output the long-wave radiation received from each one of the other surfaces, i.e. for a given surface, know how much radiation it received by each of the other surfaces?

Any advice would be highly appreciated.

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answered 2022-02-02 23:14:55 -0500

If you are using the new-ish Construction:AirBoundary object in EnergyPlus, note that the documentation says:

“The two zones separated by this air boundary will be grouped together into a combined enclosure for solar distribution, daylighting, and radiant exchange (including distribution of radiant internal gains).”

There have been some bugfixes for this object since it was first introduced, so it’s worth using the most recent version of EnergyPlus.

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Thank you for your reply; the AirBoundary object does the job in E+ 9.6. I was wondering if you have an answer for the last question in my previous comment: "Can I output the long-wave radiation received from each one of the other surfaces, i.e. for a given surface, know how much radiation it received from each of the other surfaces?"

Iason Bournas's avatar Iason Bournas  ( 2022-02-03 04:15:22 -0500 )edit

I'm not aware that that is possible.

shorowit's avatar shorowit  ( 2022-02-03 09:03:02 -0500 )edit

Thank you for informing, much appreciated!

Iason Bournas's avatar Iason Bournas  ( 2022-02-03 09:07:09 -0500 )edit

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Asked: 2022-01-20 07:33:18 -0500

Seen: 1,068 times

Last updated: Feb 02 '22