RE: [EnergyPlus_Support] DX Coils

["Michael J. Witte" <mjwitte@xxxxxxxx>]

The data that manufacturers publish is geared toward making equipment 
selections, not toward doing energy simulations.  So, it has been my 
experience that often things such as part-load curves are not 
published.

The 9.5 ton DX unit that we have developed E-Plus performance curves 
for is being used  for the IEA HVAC BESTEST E-300-E400-E500 test 
suite.  The specification for these tests include a COP degradation 
curve which we presume came from the manufacturer.  The PLF curve is: 

PLF = 0.771 + 0.229 * PLR    

There is also suggested curve in the Input Output Reference (p. 350), 
which I'm sure you saw, which is based on a single-speed residential 
unit:

PLF = 0.75 + 0.25 * PLR




On 24 Oct 2002, at 8:35, Griffith, Brent wrote:

> Mike, 
> 
> I using three sizes in this particular building, 7.5, 8.5 and 12 ton
> (nominal).  I have put together the other four performace curves for
> DX coil from MFG performace tables for many systems (these are
> actually Carrier 48TM's and 48HJ's). But so far I haven't been able to
> get data for computing Part Load curves (Do MFG's not want to put this
> data out for some reason?)
> 
> 
> I would like to get your curve for a 9.5 ton.  What I am using now is
> a linear "curve" from DOE2 (Thanks to J. Trowbridge! ) of PLF = 0.7 +
> 0.3(PLR). 
> 
> Brent
> 
> -----Original Message-----
> From: Michael J. Witte [mailto:mjwitte@xxxxxxxx]
> Sent: Wednesday, October 23, 2002 1:23 PM
> To: EnergyPlus_Support@xxxxxxxxxxxxxxx
> Subject: Re: [EnergyPlus_Support] DX Coils
> 
> 
> We have developed a PLF curve for a 9.5 ton unit which we could 
> share, but it sounds like you're looking for something larger.  The
> manufacturer should be willing to provide you with this.  What size
> range are you looking at?
> 
> Mike
> 
> 
> On 22 Oct 2002, at 11:35, Griffith, Brent wrote:
> 
> > Greetings,
> > 
> > RE: input for Coil:DX:CoolingBypassFactorEmpirical
> > 
> > Has anyone generated Part Load Fraction Correlation functions for
> > larger industrial rooftop package units?  It seems difficult to get
> > part load data for specific models.   All I have been able to come
> > up with is to generate a suitable cubic from the Part_Load Factor
> > Curve provided as Figure 1. in ARI Standard 340/360-2000.  This
> > seems to work but I am not sure if this is the way to go since it
> > often goes way below the E+ limit of 0.7.  Also I can't seem to push
> > the SHR higher than 0.75 which is less than what is indicated by the
> > equipment specs I am using.  
> > 
> > Any ideas?  Thanks in advance.  
> > 
> > Brent Griffith
> > 
> > ------------------------ Yahoo! Groups Sponsor
> > ---------------------~--> Get 128 Bit SSL Encryption!
> > http://us.click.yahoo.com/JjlUgA/vN2EAA/kG8FAA/dkFolB/TM
> <http://us.click.yahoo.com/JjlUgA/vN2EAA/kG8FAA/dkFolB/TM> 
> > --------------------------------------------------------------------
> > -~ ->
> > 
> > To unsubscribe from this group, send an email to:
> > EnergyPlus_Support-unsubscribe@xxxxxxxxxxxxxxx
> > 
> > The primary EnergyPlus web site is found at:
> > http://www.energyplus.gov <http://www.energyplus.gov> 
> > 
> > The group web site is:
> > http://groups.yahoo.com/group/EnergyPlus_Support/
> <http://groups.yahoo.com/group/EnergyPlus_Support/> 
> > 
> > 
> > 
> > 
> > 
> > 
> > Your use of Yahoo! Groups is subject to
> > http://docs.yahoo.com/info/terms/
> > <http://docs.yahoo.com/info/terms/>  
> > 
> 
> 
> 
> ========================================================
> EnergyPlus Testing and Support      
> EnergyPlus-Support@xxxxxxxx
> 


------------------------ Yahoo! Groups Sponsor ---------------------~-->
Get 128 Bit SSL Encryption!
http://us.click.yahoo.com/JjlUgA/vN2EAA/kG8FAA/dkFolB/TM
---------------------------------------------------------------------~->

To unsubscribe from this group, send an email to:
EnergyPlus_Support-unsubscribe@xxxxxxxxxxxxxxx

The primary EnergyPlus web site is found at:
http://www.energyplus.gov

The group web site is:
http://groups.yahoo.com/group/EnergyPlus_Support/




 

Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/