Large eddy simulation of inhaled particle deposition within the human upper respiratory tract

A three-dimensional (3-D) computer geometrical model of the human upper respiratory tract (URT), including the airway from mouth, pharynx, larynx and trachea to triple bifurcation was created. A large eddy simulation (LES) based on this model investigated the deposition of inhaled particles within the human URT. Steady respiration mode was first considered with three kinds of breathing intensity Q = 30, 60 and 90 L/min and then compared with an unsteady respiration mode at the breathing intensity of Q =60 L/ min. The deposition efficiencies (DEs) of different particles with density of rho = 600, 912 kg/m(3) and particle diameter of d = 1, 5, 6.5 mu m was studied, respectively. The results showed that the increases of particle diameter, particle density and breathing intensity improves the particle DEs in the human URT and the particle DEs in unsteady respiration mode are higher than those in steady mode. The results agree well with corresponding experimental data. (c) 2006 Published by Elsevier Ltd.