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<DIV dir=ltr align=left><FONT face="Lucida Console" color=#0000ff size=2><SPAN
class=981443022-29082006>All,</SPAN></FONT></DIV>
<DIV dir=ltr align=left><FONT face="Lucida Console" color=#0000ff size=2><SPAN
class=981443022-29082006></SPAN></FONT> </DIV>
<DIV dir=ltr align=left><FONT face="Lucida Console" color=#0000ff size=2><SPAN
class=981443022-29082006>Thanks for the responses on yesterday's question,
'simulating a VAV without cooling coil'. A reasonable result was obtained
by using a DX coil and setting the capacity to 1. Believe I tried sending
it to zero prior, but this as I now understand
invoked autosizing.</SPAN></FONT></DIV>
<DIV dir=ltr align=left><FONT face="Lucida Console" color=#0000ff size=2><SPAN
class=981443022-29082006></SPAN></FONT> </DIV>
<DIV dir=ltr align=left><FONT face="Lucida Console" color=#0000ff size=2><SPAN
class=981443022-29082006>Today I'd like to take a conventional VAV system
with cooling and model its performance in a displacement ventilation (DV)
configuration. OUr 'typical school' DV does not require underfloor air
distribution, so were not worried about accounting for any radiant effect.
I've read (well, skimmed) the Addison-Nall paper and they seem to explain
the issues sufficiently, but didn't see anything in there I could
explicitly apply to developing a DV
model with eQuest.</SPAN></FONT></DIV>
<DIV dir=ltr align=left><FONT face="Lucida Console" color=#0000ff size=2><SPAN
class=981443022-29082006></SPAN></FONT><FONT face="Lucida Console" color=#0000ff
size=2><SPAN class=981443022-29082006></SPAN></FONT> </DIV>
<DIV dir=ltr align=left><FONT face="Lucida Console" color=#0000ff size=2><SPAN
class=981443022-29082006>Here is what Trane has to say about modeling
displacement ventilation systems using Trace 700 (wherever they say 'underfloor'
read 'displacement'):</SPAN></FONT></DIV>
<DIV><FONT face="Lucida Console" color=#0000ff size=2>
<UL>
<LI>The air in a space supplied by an underfloor system is stratified and you
only need enough airflow to handle the temperature (loads) in the lower
stratified region. Trace (as well as the rest of the simulation programs)
assumes well mixed spaces with the same temperature at all locations.</LI>
<LI>The way to handle this is to model the lower portion (the bottom 6 ft or
so) as the height in the space. The top portion is then modeled by calling it
a plenum space (plenum of about 5 or 6 feet). Then create custom miscellaneous
loads and assign a portion of them to the plenum. The same thing can be done
with the lights. </LI>
<LI>As for the system side, choose a Constant Volume Variable Temperature
system. Go to the Temp/Humidity tab and assign a Leaving Cooling Coil Min and
Max temperature of 55°F. Under the Direct/Indirect Humidification Controls,
select "CV Mixed Air Bypass with Wild Coil Leaving Temp". </LI>
<LI>This will cause the temp off the coil to be low dewpoint, then air will be
bypassed around main cooling coil and reintroduced and mixed back in after the
main CC, which will allow the air to be supplied to the space with a
reasonable %RH at a higher temperature (60-65°F).</LI></UL></FONT></DIV>
<DIV><FONT face="Lucida Console" color=#0000ff size=2><SPAN
class=981443022-29082006>When everything is working right, for equivalent space
loads and equipment the DV model should allow a higher supply
temperature (60-65°) and thus perform with measurably greater number hours
of economizer operation than the conventional overhead distribution
system. </SPAN></FONT></DIV>
<DIV><FONT face="Lucida Console" color=#0000ff size=2><SPAN
class=981443022-29082006></SPAN></FONT> </DIV>
<DIV><FONT face="Lucida Console" color=#0000ff size=2><SPAN
class=981443022-29082006>Does anyone have a similar checklist or reference to
Trane's for doing a DV model in eQuest? After having attended a
one-day eQuest seminar, I am familiar with parameters. But I'm
not at all clear on how to assign say two thirds of the lighting load to a
parameter, and transfer it to the exhaust air.</SPAN></FONT></DIV>
<DIV><FONT face="Lucida Console" color=#0000ff size=2><SPAN
class=981443022-29082006></SPAN></FONT> </DIV>
<DIV><FONT face="Lucida Console" color=#0000ff size=2><SPAN
class=981443022-29082006></SPAN></FONT> </DIV>
<DIV><FONT face="Lucida Console" color=#0000ff size=2><SPAN
class=981443022-29082006></SPAN></FONT> </DIV>
<DIV><FONT face="Lucida Console" color=#0000ff size=2><SPAN
class=981443022-29082006>Thanks</SPAN></FONT></DIV>
<DIV><FONT face="Lucida Console" color=#0000ff size=2><SPAN
class=981443022-29082006></SPAN></FONT> </DIV>
<DIV><FONT face="Lucida Console" color=#0000ff size=2><SPAN
class=981443022-29082006>Brandon Nichols, PE<BR>Mechanical<BR>HARGIS
ENGINEERS<BR>600 Stewart St<BR>Suite 1000<BR>Seattle, WA 98101<BR>d |
206.436.0400 c | 206.228.8707<BR>o | 206.448.3376 f | 206.448.4450<BR><A
href="http://www.hargis.biz">www.hargis.biz</A><BR></SPAN></FONT></DIV>
<DIV><BR></DIV>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left>
<HR tabIndex=-1>
<FONT face=Tahoma size=2><B>From:</B> Brandon Nichols <BR><B>Sent:</B> Monday,
August 28, 2006 5:15 PM<BR><B>To:</B> 'bldg-sim@gard.com'<BR><B>Subject:</B> How
to simulate VAV systems without cooling coils in eQuest<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV><FONT face="Lucida Console" color=#0000ff size=2><SPAN
class=246095619-28082006><SPAN
class=246241300-29082006>All,</SPAN></SPAN></FONT></DIV>
<DIV><FONT face="Lucida Console" color=#0000ff size=2><SPAN
class=246095619-28082006><SPAN
class=246241300-29082006></SPAN></SPAN></FONT><SPAN
class=246095619-28082006></SPAN> </DIV>
<DIV><SPAN class=246095619-28082006><FONT face="Lucida Console"><FONT
size=2><SPAN class=246241300-29082006><FONT
color=#0000ff></FONT></SPAN></FONT></FONT></SPAN> </DIV>
<DIV><SPAN class=246095619-28082006><FONT size=+0><FONT
face="Lucida Console"><FONT size=2><SPAN class=246241300-29082006><FONT
color=#0000ff>I</FONT></SPAN>n the northwest <SPAN
class=246241300-29082006><FONT color=#0000ff>USA </FONT></SPAN>we often use
VAV systems without cooling for schools -- 100% outside air economizer
cooling, and 'off' for three months in the summer. The particular system I
want to model in eQuest<SPAN class=246241300-29082006><FONT
color=#0000ff> </FONT></SPAN>is the standard VAV with heat recovery,
but I can't figure how to either define it without a cooling coil, or render the
cooling coil and chiller ineffective.</FONT></FONT></FONT></SPAN></DIV>
<DIV><FONT face="Lucida Console"><FONT size=2><SPAN
class=246095619-28082006></SPAN></FONT></FONT> </DIV>
<DIV><FONT face="Lucida Console"><FONT size=2><SPAN
class=246095619-28082006>What is the best way to do
this?</SPAN></FONT></FONT></DIV>
<DIV><FONT face="Lucida Console"><FONT size=2><SPAN
class=246095619-28082006></SPAN></FONT></FONT> </DIV>
<DIV><FONT face="Lucida Console"><FONT size=2><SPAN
class=246095619-28082006></SPAN></FONT></FONT> </DIV>
<DIV><FONT face="Lucida Console" size=2>Thanks</FONT></DIV>
<DIV align=left>
<DIV align=left><FONT face=Arial size=2></FONT> </DIV><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial; mso-bidi-font-size: 12.0pt">
<DIV><SPAN
style="FONT-SIZE: 10pt; COLOR: gray; FONT-FAMILY: Arial; mso-bidi-font-size: 12.0pt"><SPAN
class=212011020-11052004><FONT color=#000000>Brandon Nichols,
PE</FONT></SPAN></SPAN></DIV>
<DIV><SPAN
style="FONT-SIZE: 10pt; COLOR: gray; FONT-FAMILY: Arial; mso-bidi-font-size: 12.0pt"><SPAN
class=212011020-11052004><FONT
color=#000000>Mechanical</FONT></SPAN></SPAN></DIV>
<DIV><SPAN
style="FONT-SIZE: 10pt; COLOR: gray; FONT-FAMILY: Arial; mso-bidi-font-size: 12.0pt"><FONT
color=#000080><STRONG>HARGIS ENGINEERS</STRONG></FONT></DIV>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; COLOR: gray; FONT-FAMILY: Arial; mso-bidi-font-size: 12.0pt"><FONT
color=#515151>600 Stewart Street</FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; COLOR: gray; FONT-FAMILY: Arial; mso-bidi-font-size: 12.0pt"><FONT
color=#515151>Suite 1000</FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; COLOR: gray; FONT-FAMILY: Arial; mso-bidi-font-size: 12.0pt"><FONT
color=#515151>Seattle, WA 98101<o:p></o:p></FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; COLOR: gray; FONT-FAMILY: Arial; mso-bidi-font-size: 12.0pt"><FONT
color=#515151>www.hargis.biz<o:p></o:p></FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; COLOR: gray; FONT-FAMILY: Arial; mso-bidi-font-size: 12.0pt"><FONT
color=#515151> <o:p></o:p></FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><B><SPAN
style="FONT-SIZE: 10pt; COLOR: gray; FONT-FAMILY: Arial; mso-bidi-font-size: 12.0pt">d
|</SPAN></B><SPAN
style="FONT-SIZE: 10pt; COLOR: gray; FONT-FAMILY: Arial; mso-bidi-font-size: 12.0pt">
206.436.04<SPAN class=212011020-11052004>0</SPAN>0<SPAN
style="mso-spacerun: yes"> </SPAN><B>c | </B>206.<SPAN
class=212011020-11052004>228.8707</SPAN></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; COLOR: gray; FONT-FAMILY: Arial; mso-bidi-font-size: 12.0pt"><SPAN
class=212011020-11052004></SPAN></SPAN><FONT color=#515151><B><SPAN
style="FONT-SIZE: 10pt; COLOR: gray; FONT-FAMILY: Arial; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA">o
|</SPAN></B><SPAN
style="FONT-SIZE: 10pt; COLOR: gray; FONT-FAMILY: Arial; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA">
206.448.3376<SPAN style="mso-spacerun: yes"> </SPAN><B>f <SPAN
style="mso-spacerun: yes"> </SPAN>|</B>
206.448.4450</SPAN></FONT></P></SPAN></SPAN>
<DIV> </DIV></DIV>
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