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

[EnergyPlus_Support] Re: For help:room air models



Hi
Does anyone have an idf file of a building or space with an atrium. I need to learn more about how an atrium is modeled. I have been looking at older postings and looking at different options for modeling the air flow in an atrium. 

Even if there are no example idf files with atrium, can you please point me to the idf file mentioned in this posting? 

Any pointers to papers or information as to how EnergyPlus deals with atriums is greatly appreciated.

Thanks
Sruba

--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, Yuen Liu <yli006@...> wrote:
>
> 
> Hi, Maize
> I have a look at the IDF building entries.  I think that the warnings, on average ceiling height of 42 m, was generated by your using auto-calculate for the Atrium ceiling height and  4 m for the EL1-Atrium (roof) height.
>  
> If you change the ceiling height of EL1 Atrium from 4  to 80 m, the roof of the Atrium will be move up to the top of the building.  The warning should disappear.
>  
> I have not found the infutration of the atrium of 0.4ACH, and the cause for warnings:-
>  
> 
>    ** Warning ** Inside surface heat balance did not converge with Max Temp Difference [C] =3.872E-003 vs Max Allowed Temp Diff [C] =2.000E-003   **   ~~~   **  During Sizing, Occurrence info=SUMMER DESIGN DAY IN SHANGHAI, 07/15 07:30 - 07:31
>  
> You may try increasing the timestep from 4 to 6 or 12.  The difference is very small and could ignored.
> I would like to know how you entered the building information.  Did you use another software, such as AUTOCAD?  I ask about this, because there are a number of zero coordinates entered as a very small exponential number.
>  
> EPlus allows you to define a partition (surface of another zone) so that you do not have to define a wall and a reverse wall construction.  The ceiling air space can be declared as a plenum and acts as a mixer.  In this way, the ceiling and floor are separate, and there is no need for a reverse floor or roof as construction.  
>  
> Because the ceiling height is low, you may not need to do the non-dimentional calculation for the room air temperature.
>  
> I have not found the roof-glazed atrium yet.
>  
> By dimention  in my mail, I was referring the building coordinates.
>  
> Non-dimentional height calculation,  I think, can be done for both controlled and un-controlled periods, as it is trying to take into account of the variation of temperature in a zone.  You may need to provide two patterns. 
>  
> I am still learning.  Comments from other users are welcome.
>  
> Dr. Li.
>  
>  
> 
> 
> 
> To: EnergyPlus_Support@...: liyuming1123@...: Sat, 20 Dec 2008 05:22:05 +0000Subject: [EnergyPlus_Support] For help:room air models
> 
> 
> 
> 
> Thank you!I have another problem of this model.The result shows that the cooling load of roof-glazed atrium is zero. I have set the infiltration of the atrium 0.4ACH,so it shouldn't have no cooling load. last time,I calculated the model with version2.2.the result is zero. today, I translate the model to version 3.0, but the result is still zero.I have upload the IDF file to the group, please help me see what is the problem of the model. Thank you very much!By the way, the input of dimentional room air model is the temperature gradient of conditioned period or unconditioned period?--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, Yuen Liu <yli006@> wrote:>> > > I think, you should up load the IDF file to the group so that some one can see how the dimensions are entered. Without the IDF, I cannot tell how the warning is generated. These are diffeent from your last posting. > > Dr. LI.> > > > To: EnergyPlus_Support@: liyuming1123@: Fri, 19 Dec 2008 08:18:43 +0000Subject: [EnergyPlus_Support] For help:room air models> > > > > Hello,I simulated an roof-glazed atrium with nondimentional pattern of the roomair model, but some warning are appeared and the results seemed there was no cooling load in the atrium.there are many warnings like this:Warning ** Problem in non-dimensional height calculation, too high surface:REVERSE_EL11_CORRIDOR1-ATRIUM WALL in zone: 1F_ATRIUM** ~~~ ** **** Average Ceiling height of zone is: 42.000** ~~~ ** **** Surface Maximum height is: 44.000** Warning ** Problem in non-dimensional height calculation, too high surface:REVERSE_EL11_CORRIDOR2-ATRIUM WALL in zone: 1F_ATRIUM** ~~~ ** **** Average Ceiling height of zone is: 42.000** ~~~ ** **** Surface Maximum height is: 44.000** Warning ** Problem in non-dimensional height calculation, too high surface:REVERSE_EL11 EAST WALL (G.C6.I20) in zone: 1F_ATRIUM** ~~~ ** **** Average Ceiling height of zone is: 42.000** ~~~ ** **** Surface Maximum height is: 44.000So can anyone tell me what the warnings mean? And when using nondimentional roomair models, how does the model calculate the cooling load of the Atrium?Thank you! > > > > > > > __________________________________________________________> Keep in touch and up to date with friends and family. Make the connection now.> http://www.microsoft.com/windows/windowslive/> 
> 
> 
> 
> 
> 
> 
> _________________________________________________________________
>




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

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/