Influence of Traditional and Solar Reflective Coatings on the Heat Transfer of Building Roofs in Mexico
Building roofs are sources of unwanted heat for buildings situated in zones with a warm climate. Thus, reflective coatings have emerged as an alternative to reject a fraction of the solar energy received by roofs. In this research, the thermal behavior of concrete slab roofs with traditional and sol...
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doaj-c2d4d473c9554a2ba50841d25e944db02021-04-06T23:00:23ZengMDPI AGApplied Sciences2076-34172021-04-01113263326310.3390/app11073263Influence of Traditional and Solar Reflective Coatings on the Heat Transfer of Building Roofs in MexicoIván Hernández-Pérez0División Académica de Ingeniería y Arquitectura (DAIA-UJAT), Universidad Juárez Autónoma de Tabasco, Carretera Cunduacán-Jalpa de Méndez km. 1, Cunduacán, Tabasco CP 86690, MexicoBuilding roofs are sources of unwanted heat for buildings situated in zones with a warm climate. Thus, reflective coatings have emerged as an alternative to reject a fraction of the solar energy received by roofs. In this research, the thermal behavior of concrete slab roofs with traditional and solar reflective coatings was simulated using a computational tool. The studied slab configurations belong to two groups, non-insulated and insulated roofs. In the second group, the thermal insulation thickness complies with the value recommended by a national building energy standard. Weather data from four cities in Mexico with a warm climate were used as boundary conditions for the exterior surface of the roofs. The computational tool consisted of a numerical model based on the finite volume method, which was validated with experimental data. A series of comparative simulations was developed, taking a gray roof as the control case. The results demonstrated that white roofs without insulation had an exterior surface temperature between 11 and 16 °C lower than the gray roof without insulation. Thus, the daily heat gain of these white roofs was reduced by a factor ranging between 41 and 54%. On the other hand, white roofs with insulation reduced the exterior surface temperature between 17 and 21 °C compared to the gray roof with insulation. This temperature reduction caused insulated white roofs to have a daily heat gain between 37 and 56% smaller than the control case. Another contribution of this research is the assessment of two retrofitting techniques when they are applied at once. In other words, a comparison between a non-insulated gray roof and an insulated white roof revealed that the latter roof had a daily heat gain up to 6.4-times smaller than the first.https://www.mdpi.com/2076-3417/11/7/3263solar reflective coatingsheat transferdaily heat gainscool roofs |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Iván Hernández-Pérez |
spellingShingle |
Iván Hernández-Pérez Influence of Traditional and Solar Reflective Coatings on the Heat Transfer of Building Roofs in Mexico Applied Sciences solar reflective coatings heat transfer daily heat gains cool roofs |
author_facet |
Iván Hernández-Pérez |
author_sort |
Iván Hernández-Pérez |
title |
Influence of Traditional and Solar Reflective Coatings on the Heat Transfer of Building Roofs in Mexico |
title_short |
Influence of Traditional and Solar Reflective Coatings on the Heat Transfer of Building Roofs in Mexico |
title_full |
Influence of Traditional and Solar Reflective Coatings on the Heat Transfer of Building Roofs in Mexico |
title_fullStr |
Influence of Traditional and Solar Reflective Coatings on the Heat Transfer of Building Roofs in Mexico |
title_full_unstemmed |
Influence of Traditional and Solar Reflective Coatings on the Heat Transfer of Building Roofs in Mexico |
title_sort |
influence of traditional and solar reflective coatings on the heat transfer of building roofs in mexico |
publisher |
MDPI AG |
series |
Applied Sciences |
issn |
2076-3417 |
publishDate |
2021-04-01 |
description |
Building roofs are sources of unwanted heat for buildings situated in zones with a warm climate. Thus, reflective coatings have emerged as an alternative to reject a fraction of the solar energy received by roofs. In this research, the thermal behavior of concrete slab roofs with traditional and solar reflective coatings was simulated using a computational tool. The studied slab configurations belong to two groups, non-insulated and insulated roofs. In the second group, the thermal insulation thickness complies with the value recommended by a national building energy standard. Weather data from four cities in Mexico with a warm climate were used as boundary conditions for the exterior surface of the roofs. The computational tool consisted of a numerical model based on the finite volume method, which was validated with experimental data. A series of comparative simulations was developed, taking a gray roof as the control case. The results demonstrated that white roofs without insulation had an exterior surface temperature between 11 and 16 °C lower than the gray roof without insulation. Thus, the daily heat gain of these white roofs was reduced by a factor ranging between 41 and 54%. On the other hand, white roofs with insulation reduced the exterior surface temperature between 17 and 21 °C compared to the gray roof with insulation. This temperature reduction caused insulated white roofs to have a daily heat gain between 37 and 56% smaller than the control case. Another contribution of this research is the assessment of two retrofitting techniques when they are applied at once. In other words, a comparison between a non-insulated gray roof and an insulated white roof revealed that the latter roof had a daily heat gain up to 6.4-times smaller than the first. |
topic |
solar reflective coatings heat transfer daily heat gains cool roofs |
url |
https://www.mdpi.com/2076-3417/11/7/3263 |
work_keys_str_mv |
AT ivanhernandezperez influenceoftraditionalandsolarreflectivecoatingsontheheattransferofbuildingroofsinmexico |
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