Computational fluid dynamics investigation of particle inhalability

摘要

This study uses computational fluid dynamics to investigate particle aspiration at the low air velocities typical of occupational settings.A realistic representation of a human head on a simpler geometric torso was positioned facing the wind (0.2,0.4ms~(-1)),and breathing was simulated using constant inhalation (1.8,4.3ms~(-1)).Aspiration was simulated using laminar transport for particles 0.3-116 mu m.Results from the 0.4ms~(-1)freestream and 4.3ms~(-1)inhalation rate compared well with results from the literature for smaller particles.For particles >=68 mu m,simulations yielded smaller aspiration efficiencies than reported in experiments.For all low velocity conditions studied,the aspiration efficiency curve dropped well below the 50% recommended by the ACGIH in the forward-facing orientation.Additional investigation of aspiration efficiency at other orientations relative to the wind is recommended to fully investigate aspiration efficiency for large particles in occupational environments.