[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[EnergyPlus_Support] Slab Program for small residential buildig

Hi.

Lets have a house of 5m x 6m, so the area is 30m2 and the perimeter is 
22m with no insulation. In summer, ground temperatures (2m depth, just 
as a reference) are 28.5ºC (33ºC average outside temps). The house is 
cooled to 27ºC. When using the APRatio as 10 (default), the Average 
Ground Temperatures are 24ºC, but for this small house, APRatio is 30 / 
22 = 1.36, Slab Program allows only for integer numbers greater than 1, 
so I put "2", ok? The new Average Ground Temperatures are now like 
17.5ºC. 

Using 28.5ºC gives heat flux trough ground that seems ok, using 17.5ºC 
gives a very high heat flux, how should I interpret it? As the house 
becomes smaller the ground cools intself down? In a hipotetically case 
of a 0m2 area house with hvac setpoint equalling the outside 
temperature, the Slab Ground Temperature should be the "Natural Ground 
Temperatures", shouldn't it? But it seems to me that Slab
would give the opposite result (a very cool ground).

The reference says that using SlabProgram is specially important for 
residdential applications and very small buildings but the example is 
for a big commercial building with APRatio=10.

Thanks,

Daniel



------------------------------------

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/