AW: type 56, g-value

["hotline" <hotline@xxxxxxxxxxxxxx>]

Dear Robert,

in your *.dck you only considered Qsoltr, which is the transmitted solar radiation.
If you want to calculate the solar heat gain coefficient of the used glazing you have to consider the secondary heat flux of the window as well.
Qsec is given by the NTYPE56 for the whole zone.

For your case with one window in the zone the SGHC calculates to:

SHGC   =   (Qsec+Qsoltr)/(Isol)


regards,

Matthias


-----Ursprüngliche Nachricht-----
Von: Robert Himmler [mailto:himmler@igs.bau.tu-bs.de] 
Gesendet: Freitag, 4. April 2003 17:04
An: trnsys@relay.doit.wisc.edu
Betreff: type 56, g-value


Hello TRNSYS-users,

I have a problem with type 56. I want to calculate the g-value of a window in a simple static example.

A window with a g-value of 0,33 and an area of 1 m2 (without frame) gets 360 kJ/hm2 of direct radiation (angle of incidence: 0 degrees). The room receives Qsoltr = 93,6 kJ/hm2. Thus the g-value 0,26.

Why is there a difference? I have checked it with other windows and the same mistake occures. If I use the window "without pane" I get the correct value of 360 kJ/hm2 in the room.

Can anybody help me?

Cheers,

Robert


*************************************************************

Steinbeis-Transferzentrum Energie-, Gebäude- und Solartechnik TU Braunschweig - Institut für Gebäude- und Solartechnik Dipl.-Ing. Robert Himmler Mühlenpfordtstr. 23 38106 Braunschweig

Tel 0531/391-3563
Fax 0531/391-8125

robert.himmler@stz-egs.de
himmler@igs.bau.tu-bs.de