Optimal design of complex dynamic shadings: Towards sustainable built environment

Complex dynamic shading is one of many innovative technologies widely used to improve comfort and energy saving for the construction of a sustainable built environment for modern cities. However, the dynamic mech-anism of the complex shading design has not always been well understood, which plays significant importance in the building performance of cities especially considering the complex environmental conditions. In this study, we aim to optimize the annual daylighting and energy performance of a complex, dynamic, origami-based shading system based case studies of a typical city building, which is located in the hot summer and cold winter (HSCW) zone in China. A modified parametric behavior maps (PBM) method was utilized for performance evaluation. A multivariate function was used to describe the interaction between the annual operation schedule and three environmental stimuli, i.e., hourly solar radiation reaching the south-facing window, hourly mean illuminance of the room, and hourly outdoor dry-bulb temperature. Radiance and EnergyPlus were integrated into the annual performance simulation of the dynamic shading. Experimental data has been used for validation of the dynamic strategy. The results indicated that the performance of the complex dynamic shading compared to the conven-tional static overhang shading depends largely on the annual operation schedule on an hourly basis. Indeed, the dynamic behaviors of complex shadings can improve the daylighting performance by 91.5% and energy per-formance by 19.9%, respectively, for office buildings with a large window-to-wall ratio in China's HSCW zone. This study will contribute to the performance-based design of complex dynamic shading, and further help to improve sustainability in urban design for modern cities.