[EnergyPlus_Support] Re: Opaque Surface Inside Face Conduction

["aboyemeplus" <Merid.Aboye@xxxxxxxxxxxxxx>]

Mike,

Mike,

I have implemented your suggestion below and made the model as 
simple as possible by using Regular-R materials on all construction 
elements, no internal loads, and by setting thermal absorptance to 
low values.The results obtained from design day simulations using 
this model are very similar to what I had obtained when using 
regular materials. Is there anything else that I need to set to 
force a steady-state solution?

Thank you for your support.

Merid 


 
--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, "Michael J. Witte" 
<mjwitte@...> wrote:
>
> Read carefully the definition of this report variable in the Input 
Output 
> Reference.  Because surfaces can store heat, the outside surface 
temperature 
> has little to do with the current value of inside face 
conduction.  The indoor 
> air temperature, the inside surface temperature, and the balance 
of radiant and 
> solar energy falling on the inside surface will determine the 
direction of 
> inside face conduction heat flow.  I would suggest making the 
model as simple 
> as possible (no sun, steady-state, no internal gains, and perhaps 
even set 
> thermal absorptance to something very small to minimize radiant 
transfer 
> between surfaces) to first convince yourself things are working 
OK.  Then add 
> each component back in one by one and see how things change.
> 
> Mike
> 
> 
> On 21 Jul 2006 at 21:03, aboyemeplus wrote:
> 
> > The model in question has a single zone with all its surfaces 
> > subjected to constant temperature boundary conditions.
> > During Winter design runs The "Inside Face Conduction" for all 
walls, 
> > with the exception of the floor, is Positive despite the fact 
> > that "inside wall surface temperatures" are higher than " 
outside 
> > surface temperatures" in all cases. 
> > During Summer design runs, "inside wall surface temperatures" 
are 
> > still higher than " outside surface temperatures", but this time 
> > all "Inside face conduction" rates are negative.
> > 
> > While I can make sense of the Summer design results, the Winter 
> > results are counter intuitive to me. Can someone help?
> > 
> > Thank you for your time.
> > 
> > Merid  
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> > 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.idf 
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.idf and press the "search" button.
 
Yahoo! Groups Links

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

<*> 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/