Ismail,
Type56 assumes that zones have neutral pressure. If you add air
to a zone, it is assumed that the same mass of air leaves the zone
by some means. The same would be true if you were to actively
extract air from the zone; more air would come in to replace the
air that you extracted. The issue, I think, is where the air that
comes into the zone comes from. If it comes from a humid source
then the zone humidity is going to go up. If the air comes from a
dry source then the zone humidity will go down. One of the
challenges with natural ventilation is that if the building is
cooler than the ambient when natural ventilation is activated then
humid air comes into a cool space from outside and the RH in the
space goes way up (cool air can hold less moisture than warm air).
kind regards,
David
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Dear colleagues,
I am trying to simulate the impact of natural ventilation by calculating the mean air velocity entering through the window (in m/s) according to the equation below:
I got the results as shown in attached files before and after natural ventilation. The humidity has increased enormously !
I figure out that in TRNBuild the air cannot be extracted from the zone ! How can I extract the air from a zone after activating natural or mechanical ventilation ?
Does anyone have experience to deal with such a problem ?
Thanks in advance,BestIsmail
--
************************************************Ismail OUHALLOU
Green building & Sustainability consultant
MoroccoP:+212 620 548 116F:+212 522 326 440
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-- *************************** David BRADLEY Principal Thermal Energy Systems Specialists, LLC 22 North Carroll Street - suite 370 Madison, WI 53703 USA P:+1.608.274.2577 F:+1.608.278.1475 d.bradley@tess-inc.com http://www.tess-inc.com http://www.trnsys.com