Resumo

CHAVEZ-GALAN, Jesús; ALMANZA, Rafael  e  RODRIGUEZ CUEVAS, Neftalí. Convective heat transfer coefficients: experimental estimation and its impact on thermal building design for walls made of different mexican building materials. Concr. cem. investig. desarro [online]. 2014, vol.5, n.2, pp.26-38. ISSN 2007-3011.

Some of the main factors that determine the reliability of a building's thermal design are the thermal and heat transfer properties. Some measurements were carried out to help the optimization of the thermal design process of buildings. We present experimental data on convective heat transfer coefficients for walls of diverse building materials in vertical and horizontal position using a powerful tool as it is a wind tunnel. Red brick, tepetate (limestone), adobe and concrete test walls of 0.46 x 0.56 x 0.06 m were manufactured, as well as a testing prototype to mount them and evaluate their convective heat transfer coefficients. Measurements were carried out at the wind-tunnel for a 2 - 10 m/s wind velocity interval. Reported values fluctuate between 14 - 71 W/m²K depending on material and wall position, as well as wind velocity. The impact of using experimental data versus data  recommended by Mexican standards in the thermal design of a building was evaluated through simulations with the Energy - 10 software, estimating discrepancy of energy consumption for a building at four locations in Mexico with diverse climatic and global solar irradiation conditions.

Palavras-chave : convection; heat transfer coefficients; wind tunnel; solar global irradiation; building materials.