Heat Transfer through Glass.

[kile]

My back ground is Electrical Eng but I need help, call any one tell me with proof the best form of insulating medium to be inserted to the gap between the two pains of a double glazed window.
I am hearing about Low-emittance, Argon filled and Krypton filled units.
I am looking for the one, which has the best U(Lest heat losses) value/ Msq with mathematical proofs If possible .Our a web site which shown this preferable one which is not selling a product.
Thanks alot

 

[IRstuff]

Generally, it's not worth the extra money to put in anything more fancy than air.

The simple fact is that the glass seal technology for the moderate priced windows is still not good enough to prevent the gas from leaking.

Unless you can find and are willing to pay for a fully hermetical seal...

TTFN

 

[poetix99]

...in other words, unless money is no object, use air.

If money is no object, use NOTHING - literally a vacuum for the lowest heat transfer coeff.

If there are particular concerns about radiation (at night in a desert), AND money is no object, then the emissitity of the glass might be improve in the IR spectrum with one of the gases you'd cited.

 

[MortenA]

Since glass is transperant you have to consider radiation if your are in hot areas. Thats why many high-rises i warm area have a "gold" look when seen from outside. The gold will reflect sunligt at specific wavelengths to ensure that light do come in but that most IR radiation is reflected.

Best Regards

Morten

 

[quark]

Kile!

One major problem is (particularly in pharma companies) condensation inside the double panel window. If there is a temperature difference on both sides of the panel there will be condensation on the hot side glass internally which you cannot clean.

One alternative is providing breathers from cold side into the double panel window.

Regards,

 

[IRstuff]

The reason for the condensation is failure of the gas seal and/or poor drainage of the outside frame.

When I bought my vinyl windows, I spent some time researching low-e coatings, but couldn't really do a decent comparison since each manufacturer does the math a little differently. I would at least go with a reasonably reputable or well-known glass supplier such as PPG and the like.

TTFN