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Unbalanced ventilation systems in energy plus (design builder) [closed]

asked 2015-10-03 06:09:20 -0500

Dmitry's avatar

updated 2015-10-04 08:41:44 -0500

Hi everyone, I am working with an energy model for LEED certification and since I am new to energy plus (I am using Design Builder), I was wondering what the best way to model unbalanced ventilation systems is. I have DOAS, which supplies more air than it exhausts; and exhaust only systems, some of which serve multiple zones. Overall, building's ventilation systems are balanced, so excessive supply air from some zones is to be extracted by exhaust only systems.

I have a doubt whether I should use airflow network model or I can try to indicate, that exhaust air in rooms with negative pressure is compensated with air with thermally neutral temperature. If the later approach is possible, how should I proceed with it?

Thank you, Dmitry

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Closed for the following reason the question is answered, right answer was accepted by Dmitry
close date 2015-10-11 09:14:53.120821

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answered 2015-10-08 02:06:02 -0500

Hi Dmitry,

You can use ZoneMixing (one-way flow) or ZoneCrossMixing (two-way flow) to move air between the zones, but you must specify airflow rates and schedules for this flow, and it cannot be automatically linked to HVAC system operation.

EnergyPlus airflow network model can be connected with the HVAC system, but for limited system types only (such as CAV).

Yixing Chen

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Hi Yixing, thank you for an answer and referring to ZoneMixing object.

Dmitry's avatar Dmitry  ( 2015-10-11 09:14:45 -0500 )edit

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Asked: 2015-10-03 06:09:20 -0500

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Last updated: Oct 08 '15