Measuring effects of Urban physical Components on the Thermal Comfort of Urban Open spaces (Case study: Posht-e-silo District in Yazd City)

With the advent of theories of the sustainable city, the ecological city, the smart city and the green city in recent decades, attention has been paid to nature-friendly design, ecological sustainability and climate issues. this paper is conducted with the aim of explaining the physical characteristics of the thermal areas of urban open spaces and micro-climate. the present paper is designed to extract the elements of the urban form affecting the thermal comfort of urban open spaces in the hierarchical structure of the building, using the descriptive-analytical method. This research has been carried out on a part of the 17.5 hectare of Silo District of Yazd. In the first step, using the simulation method, the average radiant temperature was calculated at the selected site , and then the thermal comfort was calculated based on the PMV index for the specific group in the warmest day of 2015. In the second part, by comparing the thermal comfort and physical factors of the environment including height, enclosure, vegetation, etc., the physical form criteria have been identified for the realization of thermal comfort. The results show that the spatial, physical and environmental dimensions of the elements of the urban form, such as enclosure (height to width H / W), visibility to the sky and the pattern of the network of passages, materials (gender, color) of the roof, body and floor, vegetation (Species and density), use and ... are among the factors affecting the comfort of the city's open spaces, due to which urban planning and design process can create spaces that provide thermal comfort to users.