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doubt gap or opening in the wall

asked 2015-06-30 21:12:48 -0500

nixon's avatar

updated 2018-07-07 10:31:53 -0500

Good day, my question is about modeling with SketchUp and plugin legacity Openstudio, as you can see in the attached image, which would be the proper way to perform the drilling of the side walls? Should i drill the wall or should i do it like a window and then put a layer of air?  the attached image

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Are you modeling physical openings with air coming through or windows with glazing?

David Goldwasser's avatar David Goldwasser  ( 2015-07-01 09:22:46 -0500 )edit

I'm modeling physical openings with air

nixon's avatar nixon  ( 2015-07-01 16:35:25 -0500 )edit

I'm doing the same thing, opening in the wall which will be best suited.

cjvl's avatar cjvl  ( 2015-07-02 20:23:00 -0500 )edit

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answered 2015-07-03 01:02:48 -0500

updated 2016-03-23 11:05:29 -0500

So I really want to let some EnergyPlus experts chime in, but I'll give some background and offer some suggestions. I assume you want to model the area between the two walls in front as a thermal zone.

  1. If you model the opening with window you will get daylight through the opening but not air
  2. You could model the wall in front as shading surfaces, but then it is only being used to shade the wall behind it. The space between the walls wouldn't be part of a thermal zone.
  3. I'm not exactly sure what would happen if you don't fully enclose the front thermal zone, but I don't think that is what you want to do.
  4. Back to item 1. If you modeled the opening as a window, you could try to set a very high infiltration for that zone, to mimic the air exchange that would normally occur.
  5. The Wind and Stack object in EnergyPlus might be a good solution, but it does have limitations. OpenStudio doesn't currently support this so you would have to add this as an EnergyPlus measure, or manually extend the IDF file to add this.
  6. Lastly, you may want to look at the Trombe Wall documentation. You could model this as a naturally ventilated trombe wall. Again, this is something not directly supported in OpenStudio, so you would need to create an EnergyPlus measure or edit an exported IDF file.
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hi david, you mentioned in your answer at point 6 that it is possible to model it as a naturally ventilated trombe wall. in that case is it mandatory to create inlet and outlet opening in trombe wall geometry physically. as well as which object i have to use for it.

muin's avatar muin  ( 2019-04-25 22:05:55 -0500 )edit

@muin as referenced in the documentation I link to the EnergyPlus installation includes a PassiveTrombeWall.idf and ActiveTrombeWall.idf example file. I would use those as patterns to follow; and read the input output reference for what is required vs. optional.

David Goldwasser's avatar David Goldwasser  ( 2019-04-26 08:47:19 -0500 )edit

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Asked: 2015-06-30 21:12:48 -0500

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Last updated: Jul 07 '18