The computational fluid dynamics (CFD) method is used to simulate the removal of fine particulate matter (PM2.5) by three displacement-like ventilation systems (horizontal supply air from the middle of the workshop and exhaust air from the upper part

horizontal supply air from the lower part of the workshop and exhaust air from the upper part

downward supply air from the lower part of the workshop and exhaust air from the upper part). Field measurements verify the accuracy of the simulation. The results show that the three displacement-like ventilation systems form pollutant stratification in the workshop

and the concentration of pollutants in the lower part is lower than that in the upper part of the workshop. Pollutants in the personnel activity area of the workshop can be reduced by 26.3%–70% by decreasing the height of the exhaust outlet. Compared with the other two ventilation systems

system 3 does not cause drafts

and it exhibits a high contaminant-removal effectiveness

which is more suitable for ventilation in industrial plants.