Fume transports in a high rise industrial welding hall with displacement ventilation system and individual ventilation units

To protect any person from exposure to the toxic and cancerous particles, welding fumes should be removed from region of respiration. In the present work, displacement ventilation system has been established within a high rise-welding hall, where welding processes cause very high welding fume emissions which flow in a thermal up-current from above the welding point to the ceiling. Numerical simulations on the air flow, thermal flow and pollutants have been conducted, showing that displacement ventilation can effectively remove the airborne pollutants from the respiration region and produce the suitable thermal stratification within the large scale industrial building space. Additionally, the personalized ventilation unit is adopted to deliver fresh air to the breathing zone. The spatial distribution of airborne pollutants is affected by the altitude of personalized ventilation annulus, which is numerically investigated to enhance the overall performance of the displacement ventilation and personalized ventilation units. Finally, on site measurements presented in this paper demonstrate the above mentioned numerical investigations. This research will be significant for the ventilation in high rise industrial buildings. (C) 2011 Elsevier Ltd. All rights reserved.