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asked 2018-08-16 11:41:49 -0500

day9914's avatar

updated 2018-08-16 11:55:40 -0500

BORM's avatar

I have a quetion between infiltration and ventilation. I'm modeling a building in OpenStudio and the building has natural ventilation. I added infiltration to the building using the method ''Space Infiltration Effective Leakage Area''. The question is: if I'm using ''Space Infiltration Effective Leakage Area'' am I modeling natural ventilation (directly from EnergyPlus) or is necessary to add ventilation to the zone?

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answered 2018-08-16 14:01:59 -0500

EnergyPlus treats outdoor air entering a zone similarly whether it is from infiltration or natural ventilation.

However, infiltration values are typically far lower than what is needed to meet the ventilation requirement, so you'll need to add more natural ventilation. You can check this by reporting the infiltration air flow rate versus the ventilation requirement from your design specification outdoor air object.

The Add Wind and Stack Open Area OpenStudio measure on BCL approximates natural ventilation assuming you don't have significant inter-zone air transfer.

If you do have significant inter-zone air transfer you'll need to use the Airflow Network in EnergyPlus, and an EMS program if you have some sophisticated logic to turn the natural ventilation on/off.

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I have applied the measure you recommended to me '' Add Wind and Stack Open Area '' but now the inside temperature in the night is more down than the outside temperature. I do not have any refigeration equiment inside the building. Other thign is that the ''zone mean aire dewpoint temperaure'' in the nigth is the same than the inside air temperature the building. do you know why this happens?. I do not know if it's because of a convection problem in the indoor air.

day9914's avatar day9914  ( 2018-08-16 21:59:56 -0500 )edit

It also happens thatThe material of building's roof is in metal (zinc) and in the night the surface temperature down to 12°C, for me this is very low.

day9914's avatar day9914  ( 2018-08-16 22:01:37 -0500 )edit

where is your building located?

mdahlhausen's avatar mdahlhausen  ( 2018-08-17 12:20:14 -0500 )edit

Colombia. Is a tropical climate. During the day the maximum environmental temperature is 32 ° C with relative humidity HR: 50% and at night the minimum environmental temperature is 20 ° C with relative humidity HR: 100 - 95%.

day9914's avatar day9914  ( 2018-08-17 15:33:53 -0500 )edit

can you recommend something for this problem ?

day9914's avatar day9914  ( 2018-08-19 10:47:05 -0500 )edit

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Asked: 2018-08-16 11:41:49 -0500

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Last updated: Aug 16 '18