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

[EnergyPlus_Support] Re: Question to Slab program

That's a good question. My slab model is setup to extend 16 m horizontally past the perimeter each on all sides and includes for 2 m vertical insulation. At the very least the model considers horizontal flow...as for vertical back up to the surface...I don't know. Thanks for the pointer to the norm. I'll be checking that out.

--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, "FrancescoP" <direzionecontraria@...> wrote:
>
> Hello Neal,
> do you consider that part of the heat flows from the internal environment towards the external air passing through the ground? That happens in particular along the perimeter.
> I know that the subject is dealt with by Annex D (Application to dynamic simulation programmes) of the European technical standard EN ISO 13370:2008 "Thermal performance of buildings - Heat transfer via the ground - Calculation methods", but I have never used it�
> Has someone got more experience?
> Best Regards
> Francesco Passerini
> 
> --- In EnergyPlus_Support@xxxxxxxxxxxxxxx, "Kruis, Neal" <neal.kruis@> wrote:
> >
> > Jean,
> > 
> > The deep ground boundary condition is a user input. You may specify either a constant temperature or a zero heat flux condition. Best practice is to specify a constant temperature equal to the average annual air temperature at the depth of either the water table, or 30 meters...whichever is closer to the slab.
> > 
> > Regarding the slab thickness, the input SLABDEPTH shouldn't have any restriction. In fact, often times, depending on the material properties of the slab, the finite difference program will have to increase the thickness of the slab to ensure a computationally stable solution. I have seen some pretty thick slabs in the program much thicker than 25 inches.
> > 
> > Hope that helps.
> > 
> > Neal Kruis
> > 
> > From: EnergyPlus_Support@xxxxxxxxxxxxxxx [mailto:EnergyPlus_Support@xxxxxxxxxxxxxxx] On Behalf Of Jean marais
> > Sent: Friday, April 20, 2012 3:57 AM
> > To: EnergyPlus_Support@xxxxxxxxxxxxxxx
> > Subject: [EnergyPlus_Support] Question to Slab program
> > 
> > 
> > 
> > Where does it take its deep ground temperatures from? the weather file?
> >
>




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

Primary EnergyPlus support is found at:
http://energyplus.helpserve.com or send a message to energyplus-support@xxxxxxxx

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 currently allowed but be mindful that not everyone has a high speed connection.  Limit attachments to small files.

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:
    EnergyPlus_Support-digest@xxxxxxxxxxxxxxx 
    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/