Thermal and daylighting evaluation of the effect of varying aspect ratios in urban canyons in Curitiba, Brazil

Abstract

Urbanization is commonly associated with densification, which may lead to vertical growth or urban consolidation. The present study evaluates the daylighting potential as a function of urban morphology for the city of Curitiba (25°25′50″ S, 46°16′15″ W). It also presents a thermal analysis for a representative street axis orientation in this location, showing indoor conditions within a test office for different aspect ratios. In Curitiba, certain street axes were designated to allow densification (in the so-called structural sector of the city). As a consequence, there is a great risk of urban canyons being formed, as local legislation does not impose height restrictions to adjacent buildings. Daylight analysis was based on software simulations with LUZ DO SOL, DLN, ECOTECT, and RADIANCE. Thermal analysis was carried out by means of computer simulations with the IDA ICE software. It was verified that diagonal axial orientations relative to the north (rotated in 45°) provide higher daylighting potentials to buildings located in urban canyons. With regard to the thermal effect of varying the aspect ratio in an east-west street axis, results confirm daylighting simulations, showing the interrelation between both comfort parameters.