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3865517 
Journal Article 
Computational fluid dynamics study of human-induced wake and particle dispersion in indoor environment 
Tao, Yao; Inthavong, K; Tu, J 
2017 
Yes 
Indoor and Built Environment
ISSN: 1420-326X
EISSN: 1423-0070 
26 
185-198 
The impact of human-induced wake flow and particle re-dispersion from floors in an indoor environment was investigated by performing computational fluid dynamics simulations with dynamic mesh of a moving manikin model in a confined room. The manikin motion was achieved by a dynamic layering mesh method to update new grids with each time step. Particle transport from the floors and its re-dispersion was tracked by a Lagrangian approach. A series of numerical simulations of three walking speeds were performed to compare the flow disturbance induced by the walking motion. The significant airflow patterns included: an upward-directed flow in front of the body combined with a high velocity downward-directed flow at the rear of the body; a stagnant region behind the gap between the legs and counter-rotating vortices in the wake region. The airflow momentum induced by the moving body disturbed PM2.5 particles that were initially at rest on the floor to lift and become re-suspended due to its interaction with the trailing wake. The residual flow disturbances after the manikin stopped moving continued to induce the particle to spread and deposit over time. The spatial and temporal characteristics of the particle dispersion and concentration showed that higher walking speed was conducive to reducing human's exposure to contaminants in breathing region. 
Computational fluid dynamics; Wake flow; Particle dispersion; Human walking; Lagrangian approach