The Impact of Urbanization on Air Flow Pattern: The Case of Rio de Janeiro

Abstract

This paper presents a comparative assessment of two urban morphologies representing the urban transformations that occurred between 1976 and 2013 in downtown Rio de Janeiro. The work documents the impact of the city morphology changes on the air flow pattern, which is known to change the energy needs at the scale of the city. Special attention is dedicated to the comfort at pedestrian level and the potential for natural ventilation in a building of reference. The study was performed by means of numerical simulations based on the RANS k-ε turbulence model. The results show an increment in wind velocity at pedestrian level and a pressure difference rise between the building facades. New high-rise buildings increase the stagnation area in the leeward region, the boundary layer height, and the turbulence level.

Natural ventilation for office building retrofit in dense urban context under hot and humid climate

“…The expansion of high-rise buildings with reduced spacing tends to minimize the urban fabric air porosity (GONÇALVES et al, 2011;TORK;TIBIRIÇÁ;TIBIRIÇÁ, 2017). As a result, air velocity and the differential pressure between facades are reduced, and stagnation zones become predominant in urban areas (NG;WONG, 2005;FONTENELLE;LORENTE;BASTOS, 2015). Santamouris et al (2001) attest that in certain regions, air velocity is reduced by up to 10 times.…”