Morphology–flow coupling in urban microclimates: a parametric framework for local wind behavior around high-rise buildings

Urban morphology significantly influences wind flow patterns within dense cityscapes, affecting ventilation, structural loads, and climate-responsive design. This study develops a systematic framework to quantify the effects of morphological parameters (MPs) such as plan area density, height ratio, façade area density, aspect ratio, and building cross-sectional shapes on local mean wind velocity around and above a high-rise building embedded within parametrically controlled urban morphologies. A total of 75 selected urban configurations were evaluated using 275 validated CFD simulations across the full wind rose with 22.5° directional increments. Four non-dimensional wind velocity metrics were evaluated at key vertical levels, including pedestrian height, canopy level, and two rooftop levels capturing near- and far-wake effects, to characterize spatial variation in local mean wind velocity relevant to pedestrian comfort, outdoor ventilation, and urban renewable energy applications. The objective is to characterize, parameterize, and quantify these effects on local mean wind behavior to provide interpretable insights for wind-aware urban design and planning. Results show strong linear decay in wind speed at pedestrian level and rooftop levels with increasing plan area density, and non-monotonic responses to height ratio, with velocity minima consistently occurring near a height ratio of 0.6 across all evaluated levels. The influence of façade density on wind behavior also varies depending on whether it is driven by plan-area density or height ratio, revealing coupled aerodynamic effects. These findings establish a foundational reference for local-level urban wind simulation. Unlike prior case-specific or isolated-building studies, this work delivers generalized insights into morphology–flow coupling through a structured parametric framework, supporting predictive modeling and resilient urban design.