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How do I model transfer air in OpenStudio?

asked 2014-10-24 15:35:22 -0600

Mel's avatar

updated 2014-10-24 16:44:08 -0600

How do I model transfer air in open studio? I have exhaust fans in the toilet rooms that draw air in through transfer grilles from the rest of the building but I think my model is balancing the air using infiltration.

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I see that this has been added in the latest release of OpenStudio (As of OpenStudio Version 2.1.0 ... Zone-to-zone transfer air (zone air mixing)) Does anyone know how to implement this?

Ski90Moo's avatar Ski90Moo  ( 2020-03-05 14:52:02 -0600 )edit

There are two OpenStudio measures on BCL that do this. Add Zone Mixing Object and Air Wall Zone Mixing.

mdahlhausen's avatar mdahlhausen  ( 2020-03-09 10:37:01 -0600 )edit

4 Answers

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answered 2014-10-24 15:51:25 -0600

updated 2014-10-24 15:54:07 -0600

The conventional method in EnergyPlus is the use the ZoneMixing object to move air between zones. OpenStudio does not expose this object, but you could add ZoneMixing directly to the idf using an OpenStudio Measure.

Or just refer to this question like Amir said.

With respect to the exhaust fan. EnergyPlus will not balance your exhaust fans with infiltration for you. If you want that you have to add the infiltration objects yourself. If you have an AirLoopHVAC based system serving the zone, EnergyPlus will decrease the return air from the zone to maintain continuity. To prevent this behavior or to balance the flow yourself with an infiltration object you need to set the Balanced Exhaust Fraction Schedule Name.

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answered 2014-10-24 15:41:03 -0600

I'm not sure how to link to previous posts, but the question "How to model transfer air in EnergyPlus" has already been asked and answered.

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answered 2014-10-25 11:06:16 -0600

BenitoDe's avatar

I am using OpenStudio 1.4 to model the HVAC system of a multi-story office building. The cooling requirements of the spaces on each floor are served by AHUs (for office spaces) and FCUs (for common areas). Fresh air or makeup air is provided by rooftop AHU units with heat pipe to the AHUs and spaces with FCUs to meet the ventilation requirements.

I understand that this configuration can be implemented in EnergyPlus using the AirTerminal:DualDuct:VAV:OutdoorAir object for the AHUs and AirTerminal:SingleDuct:SupplySideMixer object for the FCUs but these objects are not yet available in OpenStudio.

My question is if there is a workaround to set this up in OpenStudio and perhaps complete the setup in EnergyPlus if necessary. My point is to do the connections in OpenStudio which is easier to do than in EnergyPlus. Suggestions will be most appreciated.

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Welcome @BenitoDe!

FYI you're answering someone's question with your own. Please either answer the question at the top of this page or start your own using the "Ask Your Question" button at the top right. Thanks!

MatthewSteen's avatar MatthewSteen  ( 2014-10-25 11:14:52 -0600 )edit

answered 2014-10-28 08:30:02 -0600

jeanlucboeuf's avatar

updated 2014-10-28 08:37:03 -0600

Perhaps you could use export function?


jean luc boeuf val d oise

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Asked: 2014-10-24 15:35:22 -0600

Seen: 1,223 times

Last updated: Mar 05 '20