Improvement of Indoor Air Environment in a Large Welding Factory by Displacement Ventilation

The design of ventilation equipment is important because it affects the ventilation performancedirectly. To improve the ventilation efficiency of the displacement ventilation, a new ventilation system was proposed in this study. The experiment was performed to measure the fume concentration and the visibility at four points under working conditions. In experimental results, the concentration of dust with a new ventilation system was decreased by about 42-60% compared to that of the existing system. The visibility was increased by about 11-18%. Numerical analysis was conducted to solve the existing and new ventilation system performances for various wind velocities and the wind directions.In numerical results, it was found that the fumes concentration of a new system was kept much lower than that of an existing system in all cases