Generic geometrical parametric study of wind-driven natural ventilation to improve indoor air quality and air exchange in offices

Abstract

Indoor air quality significantly enhances employee productivity and well-being in offices. Existing models and guidelines emphasize wind-driven natural ventilation for air exchange and thermal comfort but often overlook detailed airflow patterns. Understanding airflow dynamics is crucial for designing healthy offices, and offering insights into air exchange processes. This information is particularly valuable in mitigating the impact of CO2 and droplet release from multiple occupants, contributing to the creation of healthier office environments. This study, thus, employs a validated CFD model to investigate the impact of geometrical parameters on wind-driven ventilation in offices. With about 150 cases representing alterations in parameters for single-sided (SV) and double-sided (DV) ventilation, a sensitivity analysis identifies key contributors to airflow patterns. Eventually, while five major categories for the airflow patterns can be identified in the DV cases (i.e., (1) without a weak zone (WZ), (2) with a dominant WZ, (3) with a WZ on bottom side, (4) with a WZ on upper side, and (5) with two WZs on upper and bottom sides), a generic airflow pattern can be barely seen in the SV cases. Moreover, in the DV cases, velocity magnitude is crucial for classification of the outputs. The leeward window geometry influences DV natural ventilation more than the windward window. Furthermore, the room dimensions impact ACH more than SF6 concentration and velocity. In the SV cases, location of the infected occupant dominates air changes per hour (ACH), and theta significantly impacts average velocity in contrast to the DV scenarios.