URBAN IMPACTS ON VENTILATION IN HOT-HUMID CLIMATES: MULTI-HEIGHT BUILDINGS IN BASRA

Farah Ahmed Thiab, Riyam Rajab Fenjan, Noor A. Almansor

Abstract


The purpose of the study was to identify the most influential urban design factors for improving ventilation in the open spaces of multi-storey residential complexes in Basra’s hot-humid climate. Methods: using a case study approach, we conducted ENVI-met v5.9 simulations for 16 models of two spaces within the “Al-Amal Residential Complex” during summer and winter. Four models reflected existing conditions, while 12 involved scenarios that adjusted building height, distance between buildings, and orientation, and were measured against environmental indicators: air temperature (Ta), wind speed (WS), sky view factor (SVF), and predicted mean vote (PMV). Results showed that building height is the most significant factor in improving ventilation and providing self-shading, followed by north-west orientation. Distance between buildings ranked last due to the trade-off between achieving urban breathing and increased solar exposure. The research recommends adopting compact vertical blocks with a north-west orientation and integrating vegetative or artificial shading to compensate for reduced self-shading and enhance social interaction.


Keywords


urban design factors; ventilation; multi-storey residential buildings; thermal comfort; ENVI-met; Basra.

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References


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