[BLDG-SIM] : eQuest Underfloor Air

[Brandon Nichols]

Hello Kendra,
 
The following is a link to a blog I've started with the intent to
eventually collect all the arcane but useful scraps information
necessary to do these energy analyses efficiently:
 
http://elcca-exchange.blogspot.com/2006/08/equest-displacement-ventilati
on.html
 
There's link within this to an Energy Designed Resources paper that I
used (Which another kind user in turn had pointed me to) to set up my
prototype displacement ventilation system.  While doing so I also found
the screenshot in eQuest 3.6 that shows the 'lighting heat to return air
or adjacent space' (i.e. plenum) option that the EDR paper does not
mention.  
 
Assigning the stratified heat fraction using this screen may prove
useful in solving your problem... but I can't state that definitively
has I haven't had the chance to really test it out.  
 
If this does indeed solve your problem and you have a moment, please let
me know... I'll be getting back the simulation business soon enough.
 
Brandon
 
 

  _____  

From: BLDG-SIM at GARD.COM [mailto:BLDG-SIM at GARD.COM] On Behalf Of Tupper,
Kendra
Sent: Monday, September 18, 2006 3:26 PM
To: BLDG-SIM at GARD.COM
Cc: kevinjm5000 at yahoo.com
Subject: [BLDG-SIM] : eQuest Underfloor Air



I'm trying to use eQuest to compare an Underfloor Air System and
conventional VAV system.  I have modeled the Underfloor case according
to the Addison/Nall paper, and am having some issues with the return air
temperatures. 

 

I have modeled two stratified zones (a lower occupied 5' zone, and an
upper 8' plenum space).  A portion of the internal gains and window
conduction is modeled in the plenum space, and the return air path is
set to PLENUM.  I expected a portion of the cooling loads to be
transferred to the return air, raising the return air temperatures, and
allowed the loads in the occupied zone to be met with a higher supply
air temp (SAT).

 

However, when I increase my SAT for the underfloor case, my cfm and fan
energy increases accordingly.  I output hourly return air temps for the
two cases and found that they were the same - adding heat gains to the
plenum space did not increase the return air temps.  Further, I adjusted
my heating and cooling setpoints for the zones, and found that the
return air temps are equal to these zonal setpoints, regardless of what
load is imposed on the plenum spaces.

 

Has anyone experienced this problem?  

 

Thanks!

 

Kendra

 

Kendra Tupper 
LEED(r) AP                
 FLACK + KURTZ  
405 Howard Street               415.398.3833 Main 
Suite 500                       415.402.5840 Direct 
San Francisco, CA 94105         415.433.5311 Fax 
http://www.flackandkurtz.com    kendra.tupper at sf.fk.com
<mailto:kendra.tupper at sf.fk.com>  
 

This e-mail may contain confidential and/or privileged information. 
If you are not the intended recipient (or have received this e-mail in
error) 
please notify the sender immediately and destroy this e-mail. 
Any unauthorized copying, disclosure or distribution of the material 
in this e-mail is strictly forbidden. 

 


==================
You received this e-mail because you are subscribed 
to the BLDG-SIM at GARD.COM mailing list.  To unsubscribe 
from this mailing list send a blank message to 
BLDG-SIM-UNSUBSCRIBE at GARD.COM


===========================
You received this e-mail because you are subscribed 
to the BLDG-SIM at GARD.COM mailing list.  To unsubscribe 
from this mailing list send a blank message to 
BLDG-SIM-UNSUBSCRIBE at GARD.COM
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20060918/8ef1909d/attachment-0002.htm>