Impact of hybrid ventilation strategies on mitigating aerosolized respiratory droplet dispersion in kitchen environments

The rapid airborne spread of SARS-CoV-2 in food preparation environments highlights the importance of effective ventilation design in kitchens, where confined layouts and multiple emission sources may increase the risk of aerosol exposure. Motivated by this challenge, the present study investigates the dispersion behaviour of cough-generated aerosols and examines the potential influence of hybrid ventilation strategies combining inlet jets, chimney exhaust, and an air curtain. The objective is to investigate the influence of source placement, inlet velocity, and multi-source emissions on aerosol transport patterns within an enclosed kitchen environment. An Eulerian–Lagrangian computational framework was employed to simulate four source configurations together with a dual-source case under mechanically ventilated conditions. The results indicate that source positioning plays a significant role in determining aerosol transport behaviour. The predicted infection risk reached approximately 68% for the dual-source configuration but decreased to about 18% when the emission source was located near the chimney exhaust, and further reduced to approximately 7% with increased inlet velocity. Higher ventilation velocity promoted faster plume removal, with chimney-proximal sources exhibiting more than 97% reduction in mean aerosol velocity. In contrast, offset source configurations resulted in weaker entrainment and prolonged particle suspension. Smaller droplets (10 µm) were rapidly removed by the ventilation flow, whereas larger droplets (50 µm) exhibited temporary recirculation before evacuation. These findings provide insight into the relative influence of ventilation configuration and source placement on aerosol transport in kitchen environments. The results should be interpreted within the scope of the simplified modelling framework adopted in the study, but they offer useful guidance for improving ventilation design strategies aimed at reducing airborne exposure in high-occupancy kitchen settings.