ZEMCH 2019 International Conference Proceedings April.2020 | Page 36
in the present research due acknowledgments obtained by the first author during her undergraduate
comfort course.
To perform the simulations procedure, site and climate conditions, beside other parameters are
required as:
● The Dogniaux synthetic solar radiation and natural light method is selected for an urban
tropical climate;
● Reflectance room data: Ceiling and window and side walls have a value of ρ = 0.70; Room
back wall (wood surface) and floor ρ = 0.20.
● The light‐shelf device tested is 2.20m from the floor, outside and indoor widths of 50cm, and
5 cm of thickness, and 50% up and down side reflectances.
● The work surface height is 0.75m
2.2. Glare Conditions Analysis
The glare is a phenomenon caused by excessive contrast of luminance [6] in an environment and
is a major source of discomfort in the work area. The indoor glare conditions caused by the natural light
incidence can be obtained by using the NatLite [4] software. These results are presented by graphical
means as glare percentage of area incident and level of impact along the daytime [7]. Itʹs important to
emphasize that the work area is height 0.75m from the floor, and the distance between the window and
the point analyzed is 4m.
2.3. Light shelf analysis for the facade of the room analyzed
The light‐shelf [8] is an architectural device that can improves better indoor light distribution,
bringing a diffuse lighting and can prevents possible glare conditions. Ideally, it should be used on the
North and South facades, due to the angle of inclination that the light reaches on the shelf. Due to the
studied building façade is Southeast oriented, tests where performed using the RadLite software to
compare the results with and without light shelf on that façade.
3. Results
3.1 Indoor daylight conditions
Are shown in figures 1a and 1.b the mesh created from the classroom area beside light quality
results (in terms of Daylight Factor). Both the rows and are spaced from the windows and 1 meter apart.
Columns have been named with letters and rows with numbers for ease of understanding. The points
together form the working area of the room, defined in accordance with the Annex A of NBR 8995‐1:
2013 [9].
3.2. Glare conditions
The result for the indoor glare conditions are presented in table 1. The graphs relate the obfuscation
values to the maximum tolerable value, before the sensation of discomfort, considering the average sky
value (typical sky of Rio de Janeiro) at over the months. For this, a reference point was set at 4 meters
from the window and equidistant from the side walls of the room (which can be identified in figures a
and b).
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ZEMCH 2019 International Conference l Seoul, Korea