Hi everybody,
I have two questions about the description of a glass facade with a
complex glass system: one about the geometry and one concerning the
material.
1-. With the objective in daylight calculations and daylight efficiency
of materials I try to simulate, so accurate as possible, a doble glazing
facade with the next composition:
9mm laminated glass with spectrally selective interlayer -- 16mm air --
4mm float glass
All the papers I've read describe the glass geometry as polygon as follows:
mod polygon id
0
0
3n x1 y1 z1
x2 y2 z2
...
xn yn zn
In my case, with such a glass system, would be this geometry
description of the glass right and accurate? or should I define the
radiance geometry like the contructed geometry?
2-. The second question is about the material description.
I have measured the transmittance of this doble glazing material sample
with a Spectrometer and an accessory for external measurements and
computed its transmissivity.
The complete definition of the material that I get is as follows:
mod glass id
0
0
3 rtn gtn btn
On the other hand I have exported in Radiance format from the software
Optics5 a similar glass, also with sun protection interlayer, and the
material description is much complexer. It is as follows:
void glass sunstop-t-silver-20_glass
0
0
3 0,205 0,222 0,239
void BRTDfunc sunstop-t-silver-20_front
10
0,325 0,281 0,197
0,188 0,203 0,219
0 0 0
.
0
9 0 0 0 0 0 0 0 0 0
void BRTDfunc sunstop-t-silver-20_back
10
0,259 0,289 0,307
0,188 0,203 0,219
0 0 0
.
0
9 0 0 0 0 0 0 0 0 0
My question is if the description I did is complete and will give an
accurate calculation.
In case it is not, how can I get the hole description with the BRTD
information if I just have the glass sample and the Spektrometer to
start and this glass is not in the IGDB?
Thank you,
Marina
--
Dipl. -Ing. (-Arch) Marina Aviles Olmos
Institute for Lightweight Structures and Conceptual Design (ILEK)
University of Stuttgart
Germany
marina.aviles at gmail.com (Radiance Mailing List)
marina.aviles at ilek.uni-stuttgart.de
www.uni-stuttgart.de/ilek