Re: [EnergyPlus_Support] Three glass glazing with extra foward mounted glass screen

["Jean Marais jeannieboef@xxxxxxxxx [EnergyPlus_Support]" <EnergyPlus_Support@xxxxxxxxxxxxxxx>]

Yeah, I've thought of that as a possibility. The external glazing (3-ply) will be treated by the program as internal glazing. That brings some implications with it as well...for one that radiation passing through internal glazing enters the zone as fully diffuse. Then I could just as well model the external shading surface with transmission. I think the local temperature behind the protective screen might be much more than Outdoor Air temperature. I have a simulation report of someone modelling the same system with far less air gaps which apparently only came to max 53ºC. If it's a hot day 32ºC and inside is 26ºC, my 3-ply Window has U=1.0 W/m²/K that would mean 6 W/m². If the 53ºC were worst case that would mean 27 W/m²...almost 5 times as much heat as a maximum error. This speaks for your zone model idea, but I don't believe the slat model works on internal glazing.

Am Sa., 25. Juli 2020 um 15:01 Uhr schrieb 'Edward G. Lyon' eglyon@xxxxxxx [EnergyPlus_Support] <EnergyPlus_Support@xxxxxxxxxxxxxxx>:

 

Jean,

 

You might try making the well-ventilated space a zone in your model with a triple glaze on one side and the single glaze on the other side.  Iâ??m not sure how to integrate the blind with a single glaze, but it should be possible to have opaque horizontal walls like light shelves even if the single glaze has to be split into segments.  You donâ??t need to condition the zone but you can provide air exchange to simulate the well-ventilated part.

 

Ned Lyon, P.E. (MA, WV)
Staff Consultant

SIMPSON GUMPERTZ & HEGER
781.907.9000 main
781.907.9350 direct 
617.285.2162 mobile 
781.907.9009 fax
www.sgh.com

Send Files

From: EnergyPlus_Support@xxxxxxxxxxxxxxx <EnergyPlus_Support@xxxxxxxxxxxxxxx>
Sent: Friday, July 24, 2020 5:17 PM
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
Subject: [EnergyPlus_Support] Three glass glazing with extra foward mounted glass screen

 

 

 

Dear Collegues,

 

I would like your thoughts on how to model a 3-ply complex glazing with external slatted blind, where a forth (well ventilated) protective glass screen sit in front of it all on the very outside.

 

I have all the IGDB data on both the external screen as well as the 3-ply system and the slatted blinds. 

 

As e+ doesn't handle slatted blinds well as interpane blindes regarding it's posittion in that setup and is restricted by max 3 pane systems, I'm thinking of modelling it as a normal 3 pane system with external blinds and then construction an external transparent surface in front of the window.

 

I remember that one can set the transmission and relection properties of such an external surface. On the one hand only diffuse radiation will hit my window as expected, but on the other hand I will probably loose any spectral effects and cancle direct beam completely.

 

Perhaps I should adjust the properties of my slatted blind to incorporated the extra blocking effect of the external glass screen?

 

I'm sure you all have some ideas...

 

Kind regards,

 

Jean

__._,_.___

---

Posted by: Jean Marais <jeannieboef@xxxxxxxxx>

---

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

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

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.

Visit Your Group

• Privacy • Unsubscribe • Terms of Use

__,_._,___