Simulation and optimization of thermal comfort in residential areas based on outdoor morphological parameters

High-density urban development is affecting the outdoor microclimate of residential areas in an uncomfortable direction. Previous research has primarily focused on modifying local functional planning and construction design, without further examining how various outdoor morphological parameters influence the outdoor thermal environment. This study was conducted in a cold northern city and found that the spatial forms of buildings have a significant impact on outdoor thermal comfort in four typical residential blocks. Block C, characterized by varied terrain, experiences extreme temperature fluctuations. The parameters Vegetation volume to built-up volume (VV2BV) and Landscape otherness (LO) significantly influenced the optimization of summer PET to 24 °C and 21 °C, respectively. Building height standard deviation (BHSD) and Cubic index (CI) had a minor impact on PET. The increase in CI is inversely proportional to the PET value, while BHSD is positively correlated. When LO is 1.6, the staggered windward surface formed by the vertical direction reduces summer PET to 20.6 °C and can increase it by 4 °C in winter. These spatial parameters are ranked in order of significance for optimizing PET as VV2BV, LO, CI, and BHSD. Relative humidity, wind speed, direct radiation, and total radiation are significant factors in the spatiotemporal distribution of PET. The objective of this study is to establish a theoretical framework for improving the thermal environment of residential areas and to provide guidance for creating comfortable urban blocks.