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How to create a void in Openstudio model

asked 2016-04-20 12:06:33 -0500

updated 2016-04-24 14:12:39 -0500

I am creating my model in OS and I have to make a void(empty hole) between zone A and B. but I do not know how to do it. Thanks in advance for any help! image description image description

Image C:ZoneVentilation:WindandStackOpenArea image description

Image D:ZoneVentilation:DesignFlowRate image description

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In OpenStudio and EnergyPlus sub-surfaces can be opaque, like the door you have shown, or translucent, like a window, skylight, or glass door. You can't directly model a hole that doesn't have anything in it, and have it behave like a true hole. Is your goal to have airflow through this "void" or do you just want it for daylighting? If you want to simulation airflow through the void there are a number of solutions. If that is what you are looking for I can add an answer listing some of the options.

David Goldwasser's avatar David Goldwasser  ( 2016-04-20 13:29:00 -0500 )edit

@David Goldwasser,Thank you dear David for your response,Actually I would like to model a hole that does not have anything in it to behave like a true hole.The goal is to have airflow through this void (and in somehow maybe it gives indirect daylighting but about daylighting I am not sure, because this void is adjacent to a long corridor where we have an artificial lighting (by electricity) an a little daylighting). Would you please list the options that can solve my problem?Thanks in advance.

4Designer's avatar 4Designer  ( 2016-04-20 16:52:12 -0500 )edit

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answered 2016-04-21 04:15:15 -0500

Urado's avatar

updated 2016-04-25 02:45:58 -0500

You can't directly create a void in EnergyPlus.

I think the idea is to create a door with no mass and a small thermal resistance. Then you can add Natural Ventilation to your zone. You have many options to set your airflow: very simple models with fixed airflow rate, variation based on wind speed and direction etc.

Edit : my answer was for an outdoor opening. Since you edited the question, it is no more accurate for an opening between two thermal zones. The two possibilities I see are either to merge your two zones to avoid this problem (if possible...) or to use the Air Wall construction with a BCL measure, as proposed here.

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@Khub ZoneVentilation:DesignFlowRate is supported directly in OpenStudio on the Zones tab. The link from @Urado describes how this works. Keep in mind, this object is independent of any voids or surfaces you draw in the model.

ZoneVentilation:WindandStackOpenArea, also described at the link above, is another option, but you would need to add that through an EnergyPlus measure.

AirflowNetwork, which is in a different group from Airflow objects is an option, but it is move involved.

David Goldwasser's avatar David Goldwasser  ( 2016-04-22 11:58:05 -0500 )edit

I have to be grateful for @Urado and @David Goldwasser, for their informative answers.But in somehow I did not get the point and I hope to get your guidane.I changed the image to make my position much more clear.

@David, about ZoneVentilation:WindandStackOpenArea: I need to create my void between zone A and B but I think this option do not care the location of my void and consider it for whole model.Regarding image C on the top.

ZoneVentilation:DesignFlowRate: I tried this one as well but This do not care the size of my void (2.5x2.7m),Regarding Image D on the top.

4Designer's avatar 4Designer  ( 2016-04-24 13:55:41 -0500 )edit

Ok, a void between two zones is a totally different case. If possible, you should consider to merge the two zones into one thermal zone, avoiding this problem (it depends on your model though).

If it's not possible you can use the Air Wall construction for your hole, with a BCL measure. More information here.

Urado's avatar Urado  ( 2016-04-25 02:35:39 -0500 )edit

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Asked: 2016-04-20 12:06:33 -0500

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Last updated: Apr 25 '16