Optimizing Pedestrian Wind Comfort via Integrated Landscapes: CFD-Based Synergy Analysis

Document Type : Original Article

Authors

1 Assistant Professor, Department of Landscape Architecture, School of Architecture and Environmental Design, Iran University of Science and Technology, Tehran, Iran.

2 Master of landscape architecture, Department of Landscape Architecture, School of Architecture and Environmental Design, Iran University of Science and Technology, Tehran, Iran.

3 3- Associate Professor, Department of Landscape Architecture, School of Architecture and Environmental Design, Iran University of Science and Technology, Tehran, Iran

Abstract

Airflow is one of the most critical components of outdoor thermal and wind comfort in urban open spaces, influenced by the complex interplay of building geometry and landscape design. The present study aims to quantitatively evaluate wind behavior and develop integrated landscape design strategies by investigating pedestrian wind comfort in the open spaces between 12 residential blocks (Omid Town, Tehran). To this end, the wind flow pattern at the pedestrian level (1.75 meters) was simulated using Computational Fluid Dynamics (CFD) in Ansys Fluent software, employing the k-ε turbulence model and based on the Davenport comfort criterion. Baseline results indicated that 40\% of the 42 measurement points exceeded the pedestrian wind comfort thresholds. Subsequently, two intervention scenarios (1: Vegetation; 2: Integrated system of vegetation and porous barriers) were evaluated. Quantitative analyses demonstrated that the integrated scenario (representing the third generation of approaches) resulted in a 67\% reduction in the number of uncomfortable points. More importantly, the synergy effect analysis revealed that the combined strategy provided a 15\% additional performance improvement beyond the linear sum of individual interventions. This superior, non-linear effect confirms the necessity of developing evidence-based design frameworks for the comprehensive management of microclimates in residential complexes.

Highlights

  • 40% of residential open spaces violate Davenport wind comfort criteria.
  • Integrated landscape systems reduced uncomfortable wind points by 67%.
  • Synergy effect provides 15% additional performance beyond linear sums.
  • Highest synergy (1.22) in building gaps allows targeted wind mitigation.

Keywords

References

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Iranian Urban Design Studies
Volume 2, Issue 2 - Serial Number 4
January 2026
Pages 257-282

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History

  • Receive Date: 01 August 2025
  • Revise Date: 18 September 2025
  • Accept Date: 04 October 2025
  • First Publish Date: 06 January 2026
  • Publish Date: 20 January 2026

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