INFLUÊNCIA DA SATURAÇÃO NAS PROPRIEDADES TÉRMICAS E ÓTICAS DE MATERIAIS POROSOS UTILIZADOS EM COBERTURAS
DOI:
https://doi.org/10.46421/entac.v18i.880Keywords:
Evaporative cooling, roofings, thermal and optical properties, energy efficiency in buildingsAbstract
Several publications have indicated the potential for reducing the thermal cooling load through the application of evaporative cooling on the building roofing. Such process consists in the dissipation of the heat absorbed in the form of latent heat, with the evaporation of water contained in porous materials. However, the absorption of water by porous materials causes a change in the thermal and optical properties of materials, related to heat absorption. Such changes may reduce the advantages of using evaporative cooling on roofings. In order to more accurately assess these variations in optical properties, the emittances, reflectances and SRIs of ceramic and fibre cement porous tiles, usually applied in the Brazilian civil construction market, were evaluated both in dry and saturated conditions. In general, there was an increase in emittance and a reduction in reflectance in all evaluated samples. Thus, with the results presented, new research on this topic can use more precise values in their estimations, implying, for example, more robust computer simulations.
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