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[TRNSYS-users] about Uw, Ug, g of window in Trnbuild



hello users,
I detected something strange about Window in Trnbuild. Or maybe I don't really understand.

I find the calculation of Uw (U-value of the window), Ug (U-value of glazing) in Trnbuild is very scientific like they depend the outdoor temperature, the wind and the insolation.

But these values are not clearly showed in Trnbuild, because I found the value (U-value of glazing) showed in the "window" was taken frow the files "W4-lib" or "Prgwin" in following location (outdoor temperature=26.7°C°, Solar (W/m².K)=0, WdSpd(m/s)=6.71, hcout, hrout,  hin = (respectively) 25.47,  3.18,  6.89).
You can find in the attached document with the location I indicated.

It's not taken from the description location at the bottom of W4-lib or Prgwin files, neither from the head of Prgwin file.
So I want to know curiously in the condition of european norm (CEN), how you defined a window and checked it (Ug, Uw) that you expected. Or more far in every different norm.

Because the U-value in these descriptions is Uw (total window) said in the tutorial of window5,
So for me, this value isn't useful because we can change the frame in the
dialogue of "window". It's only useful for me when it's Ug and showed in the glazing in the dialogue of "window"(Trnbuild). I don't know if the TRNSYS 17 can do it.

Second question is about g-value,
I don't know where is g-value from, because the two values (middle of description of one window, bottom of W4-lib, Prgwin files) are the same. If it's like U-value said in
the tutorial of window5, so it's should be used for total window, not for glazing.

After all, for me, the indication of U-value, g-value of window in Trnbuild of TRNSYS 16 is strange and not according to the Norm (International, etc.), I want to know your experiences.

Aleck


Attachment: WINDOW 4.doc
Description: MS-Word document