Performance evaluation for a coupled push–pull ventilation and air curtain system to restrict pollutant dispersion in a factory building

Abstract One of the major challenges in rapid industrial development is to maintain a healthy and safe working environment, because the working environment in factories is often contaminated with harmful pollutants, such as the paint mist particles generated in manual painting factories. To effectively dilute or remove paint mist particles distributed in the working environment, this investigation developed a ventilation system by combining a uniform push–pull ventilation system with an air curtain. The performance of the developed ventilation system in restricting paint mist particle dispersion was evaluated using computational fluid dynamics based on Reynolds-averaged Navier-Stokes equations, re-normalization group k-e equations and discrete phase particle equations. Both two- and three-dimensional transient simulations were carried out by ANSYS Fluent (Version 16.0). The numerical results showed that the dispersion of paint mist particles is higher with a higher jet velocity of the air curtain but lower with a higher air supply velocity of the uniform push–pull ventilation. Furthermore, the painting position also affected the mist pollutant concentration distribution, although the developed ventilation system was operated under the same conditions. A reasonable combination of the uniform push–pull airflow and air curtain could better control the dispersion of the paint mist particles for different painting positions; this could potentially improve the indoor air quality and environmental health in painting factories, as compared with existing ventilation systems.