[EnergyPlus_Support] Re: Autosizing and general E+ procedure

["maenebraska" <maenebraska@xxxxxxxxx>]

I understand that for an annual simulation run time may not be 
significantly altered; however for runnning optimizations E+ is 
called upon 200+ times for a daily simulation.  This becomes the 
limiting factor in our test.  If I can reduce the run time down to 
under 1 minute, the optimization can be exponentially reduced in 
time.

Thank you for your fast response.

--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, "Michael J. Witte" 
<mjwitte@...> wrote:
>
> I am surprised that autosizing would add significantly to run 
time.  Sizing 
> performs a loads-only (purchased air simulation) for each 
DesignDay, then calls 
> the systems once-through to size components.  
> 
> All of the computed sizes are reported in the eio output file and 
once these 
> are determined, they are fixed for the entire simulation - nothing 
is changing 
> over the course of the year.  
> 
> The procedure for using hard sizes would be to take the values 
reported in the 
> eio ouput component sizing reports and copy/paste them into the 
idf file, 
> replacing each instance of "autosize".  I doubt that you will find 
much 
> difference in run-time between the autosized and hard-sized 
versions of the 
> input, but if you do, please send me the input files for further 
investigation.
> 
> Mike
> 
> 
> On 20 Apr 2007 at 15:24, maenebraska wrote:
> 
> > I understand that it may not be necessary to remove the 
autosizing 
> > parameters; however, the run time is too excessive when using 
the 
> > system, plant, and zone sizing in the run parameters.  Is there 
a 
> > reccommended procedure for implementing values in place of the 
> > autosizing numbers that will allow me to run the model without 
these 
> > run control features active?  It seems that I should be able 
to "size" 
> > the plant once based off of typical equipment parameters for a 
> > building of some cooling load and keep those parameters for each 
day 
> > of the year.  
> > Is there any critical limiting factors that would keep me from 
setting 
> > the coil and cooling tower characteristics constant throughout 
the 
> > simulation year?
> > 
> > Thank you in advance?
> > 
> > Dan
> > 
> > 
> > 
> > The primary EnergyPlus web site is found at:
> > http://www.energyplus.gov
> > 
> > The group web site is:
> > http://groups.yahoo.com/group/EnergyPlus_Support/
> > 
> > Attachments are not allowed -- please post any files to the 
appropriate folder
> > in the Files area of the Support Web Site.
> > 
> > EnergyPlus Documentation is searchable.  Open EPlusMainMenu.pdf 
under the
> > Documentation link and press the "search" button.
> > 
> > Yahoo! Groups Links
> > 
> > 
> > 
> > 
> > 
> 
> 
> ========================================================
> Michael J. Witte, GARD Analytics, Inc.
> EnergyPlus Testing and Support      
> EnergyPlus-Support@...
>




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

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

Attachments are not allowed -- please post any files to the appropriate folder in the Files area of the Support Web Site.

EnergyPlus Documentation is searchable.  Open EPlusMainMenu.pdf under the Documentation link and press the "search" button.
 
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/EnergyPlus_Support/

<*> Your email settings:
    Individual Email | Traditional

<*> To change settings online go to:
    http://groups.yahoo.com/group/EnergyPlus_Support/join
    (Yahoo! ID required)

<*> To change settings via email:
    mailto:EnergyPlus_Support-digest@xxxxxxxxxxxxxxx 
    mailto:EnergyPlus_Support-fullfeatured@xxxxxxxxxxxxxxx

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

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