A tempo-spatial modelling framework to assess outdoor thermal comfort of complex urban neighbourhoods

Abstract

Outdoor thermal comfort (OTC) has a significant effect on the health and well-being of urban dwellers. One of the key factors contributing to the tempo-spatial variation of thermal comfort in urban neighbourhoods is the geometrical characteristics. This paper develops a novel modelling framework to comprehensively evaluate the tempo-spatial thermal comfort performance of neighbourhoods on the basis of geometrical features. A weighted temporal thermal comfort performance (TCPw) metric is furthermore proposed to translate the thermal comfort results to a comparative performance criterion. Universal thermal climate index (UTCI) is the index chosen as baseline for assessing this metric. To demonstrate the practicality of the developed framework, three urban areas with different morphological character in climate zone of Tehran are investigated. Different geometrical variables of these locations are initially extracted from existing datasets using geographic information systems (GIS). A high-resolution spatial model is then developed to simulate thermal comfort of the neighbourhoods by coupling an energy simulation model (EnergyPlus) and a thermal comfort plugin (Ladybug). The model is successfully validated against a series of in-situ measurement data. Results indicate that differences in comfort performance are related to the simultaneous effects of neighbourhoods' layout (density, open areas), and street canyons' profiles (aspect ratio, orientation).