Effects of contaminant diffusion on the fresh air inlets of a clean room workshop

In this study, a clean workshop is the subject of our research study, and computational fluid dynamics methods are applied to investigate the effect of exhaust pipe height, exhaust velocity, barrier structure, and wind direction on contaminant diffusion from the clean workshop. Results show that an increase in exhaust pipe height and exhaust velocity or a decrease in barrier height can effectively reduce the pollutant concentration at each fresh air inlet (FAI). Along the wind direction, the contaminant concentration initially increases and then decreases as distance increases. When the height of the exhaust pipe reaches 45 m, the effect of pollutants on the FAI is insignificant. When the exhaust velocity reaches 12 m/s, the effect of pollutants on the FAI weakens as the emission speed of flue gas increases. Reducing the height of the barrier to 29–31 m can effectively improve the concentration of pollutants at each FAI. Practical implications The mechanism by which the exhaust pipe height, exhaust velocity, barrier structure, and wind direction affect pollutant diffusion from a clean room workshop is systematically investigated by combining the CFD methods with an actual clean workshop as the research object, and the optimal pollutant reduction conditions are presented, thus providing scientific guidance for the construction of clean plants and the reduction of pollutant emissions.