On the oversimplification of neighborhood impact in urban microclimate and building energy models

Rapid urbanization has led to compact cities characterized by vertical structures and complex layouts. These structures influence the urban wind environment (UWE), generating complex airflow patterns and heightened turbulence due to the uneven and heterogeneous distribution of buildings. The UWE plays a critical role in building energy performance by affecting natural ventilation, air infiltration, and convective heat transfer across building envelopes. Despite its importance, most current building energy simulation (BES) tools do not account for the effects of UWE on energy consumption in buildings situated within varying urban configurations. To address this gap, the present study investigates how urban form influences energy performance in a mid-rise district of Amman, Jordan. A representative building was selected and analyzed within five subregions, each exhibiting distinct physical characteristics-including variations in block number, average height, and built-up area-reflecting a range of urban morphologies. Computational Fluid Dynamics (CFD) simulations were conducted under multiple wind directions and speeds to evaluate wind velocity, surface pressure coefficients (Cp), and convective heat transfer coefficients (CHTCs) around the building. These data were then transferred to DesignBuilder for a comprehensive building energy performance analysis on a single representative hottest day. The findings reveal that urban morphology significantly modifies wind flow patterns, affecting wind speed, CHTC, and Cp distribution. Incorporating CFD-derived CHTC values into the BES model showed that building energy consumption could increase by as much as 49 %.