Modelling of Egyptian low-cost-housing natural ventilation: Integration of geometry, orientation and street width optimization

Starting from year 1995, 50 thousand low-cost housing units were been proposed to be built In Egypt by 2020 to overcome housing problems, only 60% have been already implemented. Three prototypes are amongst the most frequently built ones by the Egyptian government. In this research, these prototypes have been subject to natural ventilation modelling optimization based on three parameters which are geometry, orientation and the ratio between height and street width H/W using computational fluid dynamics (CFD) standard steady-state K-epsilon turbulence model and standard near wall function by adopting de-coupled approach. This approach indicates that the study is conducted in two levels: Firstly, the resulted pressure values on both sides of each prototype (the windward and the leeward walls) are measured numerically. Secondly, airflow rates inside buildings are calculated using Bernoulli equation. Results have been compared to each prototype's natural-ventilation requirements. In-situ measurements have been conducted to ensure adequate accuracy of calculations. Results of the study showed that further modifications have to be considered in the future configurations of these buildings.