Effect of thermal radiation on exterior building surfaces

Effect of thermal radiation on exterior building surfaces

Paper in proceedings (conference paper)

The improvement of thermal technical properties of insulation layers is a crucial point of reconstruction of all building objects, in the first place of the large block of flats from the socialistic period in Czechoslovakia, with the aim to extend their lifetime. However, a typical phenomenon of such reconstruction is the occurrence of algae on the outer surface of the new insulation system and conse-quently their surface degradation. This phenomenon can be explained by the night condensation of vapour from porous material structures, driven by the heat radiation. The mathematical model of evolu-tion of temperature and moisture fields is based on the physical laws of conservation of mass and energy. The numerical simulation of this process, coming from the method of discretization in time and from the finite difference method, makes use of the original software, written in the Pascal code. The comparsion of result from numerical simulation and laboratory experiments leads to some recommendations, how to avoid the algae coatings.

The improvement of thermal technical properties of insulation layers is a crucial point of reconstruction of all building objects, in the first place of the large block of flats from the socialistic period in Czechoslovakia, with the aim to extend their lifetime. However, a typical phenomenon of such reconstruction is the occurrence of algae on the outer surface of the new insulation system and conse-quently their surface degradation. This phenomenon can be explained by the night condensation of vapour from porous material structures, driven by the heat radiation. The mathematical model of evolu-tion of temperature and moisture fields is based on the physical laws of conservation of mass and energy. The numerical simulation of this process, coming from the method of discretization in time and from the finite difference method, makes use of the original software, written in the Pascal code. The comparsion of result from numerical simulation and laboratory experiments leads to some recommendations, how to avoid the algae coatings.

thermal irradiation, heat transfer

thermal irradiation, heat transfer

ŠŤASTNÍK, S.; STEUER, R.

19.09.2007

Vysoké učení technické v Brně, Fakulta stavební

Brno

978-80-214-3475-2

Sborník XII. symposia SILICHEM 2007

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