During the past decades buildings have become one of the highest energy demanding component of cities, hence alternatives solutions been sought to reduce their impact. This study presents an experimental evaluation to improve the thermal performance of roofs in semi-arid climate conditions when Phase Change Material (PCM) and natural ventilation are combined. In addition, the results evaluated the thermal comfort under an adaptive model. The performance of two modules (base and PCM) were defined as a function of indoor air temperature, lag time at peak temperature, surface temperature, and heat flux. Four configurations were evaluated: continuous roof components (Cases A) and with an air gap in the roof (Cases B), both with and without natural ventilation. The results, for the configurations with PCM, showed a maximum indoor air temperature reduction between 3.94% and 7.02% and a peak lag time between -10 and 70 min. Likewise, an increase in the solidification time of PCM between 19 to 41% was observed with natural ventilation. The configuration of PCM with 30 cm air gap without natural ventilation obtained the best result, reducing the maximum interior air temperature by up to 2.5°C, 6.85% cooling load reduction, and thermal comfort improved by 50 minutes.

在过去的几十年中，建筑物已成为城市中能源需求最高的组成部分之一，因此寻求替代解决方案以减少其影响。本研究提出了一项实验评估，以在相变材料 (PCM) 和自然通风相结合的情况下改善半干旱气候条件下屋顶的热性能。此外，结果评估了自适应模型下的热舒适性。两个模块（基础模块和 PCM）的性能被定义为室内空气温度、峰值温度滞后时间、表面温度和热通量的函数。评估了四种配置：连续屋顶组件（案例 A）和屋顶中有气隙（案例 B），有和没有自然通风。结果，对于使用 PCM 的配置，显示最大室内空气温度降低了 3.94% 到 7.02%，峰值滞后时间在 -10 到 70 分钟之间。同样，通过自然通风观察到 PCM 的凝固时间增加了 19% 到 41%。无自然通风的 30 cm 气隙 PCM 配置取得了最佳效果，最高可降低车内空气温度 2.5°C，减少 6.85% 的冷负荷，热舒适度提高 50 分钟。