Effects of internal wall design on cross-ventilation of an isolated building.

Poorly designed internal walls deter natural ventilation of buildings, causing poor indoor air quality and exorbitant energy costs when mechanical ventilation systems are used. Although one can design internal walls with minimum adverse effects on natural ventilation by controlling height, width, location, and porosity of internal walls, less research has been done to date. This study investigated how these four parameters individually and collectively influence the cross-ventilation of buildings using Reynolds-average Navier–Stokes equation-based computational fluid dynamics simulations and the local and global sensitivity analysis. When considering individual parameters, the local sensitivity analysis revealed the positive correlation between internal walls' porosity and cross-ventilation, similar to previous studies. However, the global sensitivity analysis identified the location as the most influential design parameter for cross-ventilation. Furthermore, the global sensitivity analysis revealed nonlinear, non-monotonic, and interactive relations between cross ventilation and all parameters but porosity, highlighting the importance of evaluating all design parameters together and the difficulty in extrapolating the findings for idealized to actual internal wall designs. Based on the findings, this study proposes narrow internal walls with high porosities built away from ventilation openings as a basic internal wall design to maximize the cross-ventilation of buildings. [ABSTRACT FROM AUTHOR]