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arXiv · 2510.11247

Impact of Wind Direction on Flow Over a Realistic Urban Area: A Large-Eddy Simulation Study

Ivette Rodríguez·Josep Maria Duró·Ernest Mestres·Ming Teng·Oriol Lehmkuhl
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Abstract

We conducted high-resolution large-eddy simulations over a real urban district in Barcelona to examine the impact of wind direction on near-ground flow. The computational mesh resolves over 500 million degrees of freedom, with a spatial resolution on the order of 1 m at pedestrian level. This allows a detailed analysis of mean velocity and turbulence patterns within the canopy layer. Although instantaneous flow fields differ significantly between cases, double-averaged profiles of velocity and turbulence intensity remain remarkably consistent across all wind directions. The results reveal a shear-driven mixing layer below the average building height and turbulence maxima near the tallest buildings, highlighting the influence of urban morphology on the development of flow and turbulence.

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Ivette Rodríguez, Josep Maria Duró, Ernest Mestres, Ming Teng, Oriol Lehmkuhl. 2025-10-13. Impact of Wind Direction on Flow Over a Realistic Urban Area: A Large-Eddy Simulation Study. https://arxiv.org/abs/2510.11247

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