Combining the Radiative; Conductive and Convective Heat Flows in and Around a Skylight

Martin Fält
Thermal and Flow Engineering, Department of Chemical Engineering, Åbo Akademi University, Finland

Ron Zevenhoven
Thermal and Flow Engineering, Department of Chemical Engineering, Åbo Akademi University, Finland

Ladda ner artikelhttp://dx.doi.org/10.3384/ecp110574027

Ingår i: World Renewable Energy Congress - Sweden; 8-13 May; 2011; Linköping; Sweden

Linköping Electronic Conference Proceedings 57:47, s. 4027-4032

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Publicerad: 2011-11-03

ISBN: 978-91-7393-070-3

ISSN: 1650-3686 (tryckt), 1650-3740 (online)


Normal skylights bring light into the spaces located below them. By the use of infrared radiation (IR) transmissive polymer films and IR-emitting and absorbing gases; an advanced version of the skylight may supply cooling and thermal insulation to the room located below it. This novel radiative skylight can; in its cooling mode; lead heat from the room below; to the cool skies located above the skylight. When cooling is no longer needed or attainable this connection will be cut; thus providing the room with an optimal amount of thermal resistance. This article is a progress report on the modeling of the skylight. The main work is done to combine the different heat transfer methods into one single model by the use of the commercial program Comsol 4.1. The results show that a cooling effect of 100 W/m2 is achievable when the skylight is compared to a similar skylight containing only air.


Radiative cooling; heat transfer in participating media; skylight


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