Inaccuracies Caused by Non-Uniform Luminance Distribution of Artificial Sky Dome at Scale Model Measurements

Abstract:

The primary objective of daylighting measurements, by means of physical models, is the experimental finding of daylight conditions in the interior (in case of scale model of a specific room), or their impact on the surrounding buildings (in case of models of whole buildings). If these measurements are carried out even at the early stage of the building design, they can be very helpful in revealing gross deficiencies of the design or optimization of window apertures. According to the purpose of the measurement, physical models can be placed either on site of the future building – which advantage is the possibility of a reliable reproduction of the actual shading conditions, respectively the amount of reflected light by the envelop of existing buildings – or in laboratory, under artificial sky. The advantage of measurements using artificial skies is mainly the possibility to imitate the conditions of CIE overcast sky, thus the disadvantages of the variability of natural daylight are eliminated, while there is also a potentiality to optimize different solutions at the same boundary conditions. On the other hand, if the luminance distribution of the artificial sky is does not correspond with the theoretical luminance distribution of CIE overcast sky, the results of the measurements can be incorrect. The aim of this contribution is to illustrate through a case study, the importance of ensuring the appropriate boundary conditions at scale model measurements.

• Periodical: Applied Mechanics and Materials (Volume 820)
• Pages: 411-416
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.820.411
• Online since: January 2016
• Authors: Kristián Kondáš*, Stanislav Darula, Martin Lopušniak
• Keywords: Artificial Sky, Daylight Factor, Luminance Distribution, Scale Model

References

[1] M. Bodart et al., Design of a new single-patch sky and sun simulator, Lighting Research and Technology. 38 (2006) 73-89.

DOI: 10.1191/1365782806li157oa

[2] R. Kittler, New artificial overcast and clear sky with artificial sun for daylight research, Lighting Research and Technology. 4 (1974) 227-229.

DOI: 10.1177/096032717400600407

[3] STN 73 0580-1: 1987, Denné osvetlenie budov. Časť 1: Základné požiadavky (Daylighting in buildings. Part 1: Basic requirements), ÚNM, Praha, (1987).

[4] STN 73 0580-2: 2000, Denné osvetlenie budov. Časť 2: Denné osvetlenie budov na bývanie (Daylighting in buildings. Part 2: Daylighting of residential buildings), SÚTN, Bratislava, (2000).

[5] R. Kittler, S. Darula, R. Perez, A set of standard skies, Polygrafia SAV, Bratislava, (1998).

[6] ISO 15469: 2004 (CIE S 011/E: 2003), Spatial distribution of daylight – CIE standard general sky.

DOI: 10.25039/ds011.2003

[7] STN 73 4301: 2005, Budovy na bývanie (Dwelling buildings), SÚTN, Bratislava, (2005).

[8] M. P. Duboisová Petrofová, Ľ. Selcová, Podkrovia, second ed., Jaga, Bratislava, (2005).

[9] M. Bodart, A. Deneyer, A guide for the building of daylight scale models, PLEA2006: The 23rd Conference on Passive and Low Energy Architecture, Geneva (2006) 1-6.

[10] M. Bodart et al., A guide for the building of daylight scale models, Architectural Science Review, University of Sidney, Sydney, (2007).

[11] R. Kittler, L. Kitterová, Návrh a hodnotenie denného osvetlenia, first ed., Slovenské vydávateľstvo technickej literatúry, Bratislava, (1968).