Evaluation of thermal comfort and air changes in indoor environments with solar chimneys

Abstract The use of natural ventilation strategies to provide thermal comfort and air changes is necessary in most of the Brazilian territory. In this context, solar chimneys can promote benefits such as increase air changes and enhance the thermal comfort of building users. This paper aims to investigate the ability of a solar chimney model to provide thermal comfort and air changes in classrooms and offices. We ran two stages of energy performance simulations on EnergyPlus: the first stage evaluated parameters such as height, number of installed devices per room and solar orientation aimed at providing more hours of comfort and air renewal in four Brazilian cities; the second stage expanded the scope of the devices/rooms simulated to eight Brazilian cities. In the second evaluation, the variation of climate conditions had an impact of up to 80% on comfort hours. The influence of the devices led to an average increase of 28% in comfort in classrooms and 21% in offices. The air change rates were between 2.4 and 13.5 ACH. The best performances were observed in the cities in ZB1, ZB2, ZB3, ZB4, and ZB5, demonstrating the potential benefits using this solar chimney in those bioclimatic zones.摘要 在巴西绝大部分领土范围内，采用自然通风策略以保障热舒适与换气需求是必要之举。在此背景下，太阳能烟囱（solar chimney）可带来诸多益处，例如提升换气量并改善建筑使用者的热舒适体验。本研究旨在探究一款太阳能烟囱模型在教室与办公场所中实现热舒适与换气效果的能力。我们基于EnergyPlus开展了两阶段的能源性能模拟：第一阶段针对巴西四座城市展开参数评估，评估维度涵盖设备高度、单房间安装设备数量以及太阳朝向，目标是在对应场景中实现更长的舒适时长与更优的空气更新效果；第二阶段将模拟的设备-房间场景范围拓展至巴西八座城市。在第二阶段评估中，气候条件的变化对舒适时长的影响最高可达80%。设备的应用可使教室的热舒适时长平均提升28%，办公场所则平均提升21%。空气交换率（Air Changes per Hour, ACH）介于2.4至13.5之间。ZB1、ZB2、ZB3、ZB4及ZB5气候区的城市表现最佳，这表明在这些生物气候区应用该太阳能烟囱具备可观的潜在应用效益。