[TRNSYS-users] transparent insulation

[Diego A. Arias]

Hi Irene,

I have not seen a reply to your question. When the building model was 
written, who would have thought that someone wanted transparent 
insulation? ;-)

Here are my humble ideas. I will appreciate if someone else has a better 
answer to share it with the mailing list.

Having transparent insulation will affect your energy balance on the 
wall in two ways: modifying the incoming solar radiation and the overall 
heat transfer coefficient.  My idea is to do the following:
- In TrnBuild, add the layered wall without the layer corresponding to 
the transparent insulation.
- Select the external heat transfer coefficient to be an input.  You 
will have to calculate it outside of TRNBuild, with an equation, taking 
into account the resistance of the insulation.
- To address the effect of the optical properties on the solar 
radiation, you can use Type35 (window) to calculate the transmitted 
energy through a very simple glazing system; the simplest mode uses the 
index or refraction of the material to calculate the transmissivity.  
You can then use this modified solar radiation as the solar radiation 
hitting on your insulated wall.  NOTE: set the area of the window to 1 
m^2, because the output of Type35 is energy and not energy per unit area.

This approach is an approximation. You will have to work out the 
details. For example, you can complain that the external heat transfer 
coefficient will be applied to a different temperature on the surface of 
the wall. 

Please let me know if this helps.
Best regards,

Diego


Irene Koronaki wrote:

>Dear Trnsys Users,
>How do we simulate transparent insulation? Is there any type that should be
>connected to Type56?
>Thank you in advance for your help.
>
>
>Irene P.Koronaki
>Dr. Mechanical Engineer
>Department of Building Applications
>Centre for Renewable Energy Sources
>19th klm Marathonos Ave.,
>Pikermi, 19009, Greece
>Tel: +30 210 6603255, 6603300
>Fax: +30 210 6603305
>Email: ikoron at cres.gr
>URL: www.cres.gr 
> 
>
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>TRNSYS-users mailing list
>TRNSYS-users at engr.wisc.edu
>https://www.cae.wisc.edu/mailman/listinfo/trnsys-users
>  
>


-- 

Diego A. Arias
TRNSYS Coordinator
Solar Energy Laboratory
University of Wisconsin - Madison
1500 Engineering Drive
Madison, WI 53706