CFD simulation for pedestrian wind comfort and wind safety in urban areas: General decision framework and case study for the Eindhoven University campus

Wind comfort and wind safety for pedestrians are important requirements in urban areas. Many city authorities request studies of pedestrian wind comfort and wind safety for new buildings and new urban areas. These studies involve combining statistical meteorological data, aerodynamic information and criteria for wind comfort and wind safety. Detailed aerodynamic information can be obtained using Computational Fluid Dynamics (CFD), which offers considerable advantages compared to wind tunnel testing. However, the accuracy and reliability of CFD simulations can easily be compromised. For this reason, several sets of best practice guidelines have been developed in the past decades. Based on these guidelines, this paper presents a general simulation and decision framework for the evaluation of pedestrian wind comfort and wind safety in urban areas with CFD. As a case study, pedestrian wind comfort and safety at the campus of Eindhoven University of Technology are analysed. The turbulent wind flow pattern over the campus terrain is obtained by solving the 3D steady Reynolds-averaged Navier-Stokes equations with the realisable k- ε model on an extensive high-resolution grid based on grid-convergence analysis. The simulation results are compared with long-term and short-term on-site wind speed measurements. Wind comfort and wind safety are assessed and potential design improvements are evaluated. The framework and the case study are intended to support and guide future studies of wind comfort and wind safety with CFD and, this way, to contribute to improved wind environmental quality in urban areas.