modeling particle deposition in the respiratory system during successive respiratory cycles

This study uses a 5-lobe symmetric model to investigate total, lobar and generational particle deposition fractions in the lungs during successive cycles. it was found that for the particle size between 0.05 and 2 μm and the tidal volumes greater than 1000 ml, the effect of successive cycles helped predict more deposition fraction per cycle up to about 16% than that of a single cycle. the mentioned range of tidal volumes corresponds to light or heavy physical activities. therefore, it can be understood that people, when physically active, exposed to particulate matter within the mentioned size range are at higher health risk as compared to both the resting state and the same state calculations based on a single cycle. finally, total and generational remaining mass fractions suspended in the respiratory tract after the completion of each cycle are calculated. this remaining mass fraction turned out to be negligible except for particles between 0.05 and 2 μm.