The quality of thermal environment in outdoor spaces greatly affects pedestrians' health and their reaction to microclimatic conditions, ultimately influencing their likelihood of spending time in those areas. The significance of these issues in urban environments has prompted worldwide research on microclimates and outdoor thermal comfort (OTC), establishing it as a key focus in sustainable urban design. A critical principle in designing these spaces is to prioritize thermal comfort (TC), which enhances environmental quality and boosts user satisfaction. This study seeks to examine the thermal performance of different pedestrian configurations through numerical simulations conducted with ENVI-met software, focusing on hot-semi-arid climatic conditions. This study utilizes PET (Physiological Equivalent Temperature) index, which is widely regarded as one of the most thorough approaches for estimating TC. Field measurements were taken at six locations along the canyon in Ilam city over the course of two days: one hot and one cold. TC was assessed using PET index, calculated with Rayman software based on output data from ENVI-met. Finally, 8 scenarios were simulated to improve TC conditions, focusing on the geometry of trees, shading, and the albedo of canyon materials. The study found that a horizontal shading structure measuring 3.25 meters in height is the most effective, reducing PET by 2.9°C. Additionally, materials with an albedo of 0.8 decrease PET by an average of 4.8°C compared to materials with an albedo of 0.5. Furthermore, combining Plane and Pine trees significantly improves TC, with Pine trees reducing PET by up to 5°C on hot days.
