Wind comfort assessment of a newly designed tower with a vertical green park

An emerging type of architecture, aimed at multiplying the presence of forests and trees in cities through vertical green buildings, arose in the last decade. While green roofs are nowadays quite common, architectural design calling for more holistic green parts in buildings is still in its early days, promoting the benefits of plants incorporated into buildings as protection of habitats, heat island reduction and biophilic design. The needs of creating permeable and green spaces was further emphasized by the Covid-19 outbreak, which definitely arose questions about the efficiency of mechanical ventilations systems and the exigence of finding new energy saving strategies. However, whilst green spaces generally make buildings and cities more ecofriendly, it is insufficiently known to which extent the surrounding environment and the vegetation may positively or negatively influence the pedestrian-level wind comfort quality of buildings amidst historical and well-settled urban layouts. This was the scope of the present study for which wind- tunnel (WT) testing and 3D Reynolds-averaged Navier-Stokes (RANS) simulations were performed on two facing towers in Medellìn (Colombia), in order to (i) investigate the wind field and the pedestrian-level wind comfort around the towers; (ii) to compare the performance of WT and 3D RANS for wind comfort analysis; (iii) to evaluate the impact of the environment surrounding the two towers and (iv) the mitigation effects of vegetation on wind comfort.