Case Studies in the Human Respiratory System - Computational Fluid and Particle Dynamics in the Human Respiratory System - page 279

Fig. 8.39 Frontal view
showing the nanoparticle
deposition in maxialliary
ostium and sinus for the a
right nasal cavity, and b the
left nasal cavity at 10 L/min.
Different sized particles are
coloured as follows: 1 nm red
circle; 10 nm blue square;
40 nm black triangle
found concentrated within the ostium. Thus it appears that despite a lower flow rate,
there is a lack of particle deposition within the maxillary sinus.
For a flow rate of 10 L/min it can be seen that 1 nm particles are captured within
the narrow ostium and in fact don't make it through to the maxilliary sinus. For
the left maxilliary sinus, no particles were able to pass through the ostium, but a
larger percentage of particles < 0 . 5 % deposited within the ostium alone. This is
mainly due to the curved geometry and longer ostium length providing a narrow
tube passageway for the particles to diffuse onto. These results support the report by
Hood et al. (2009), that ostium sinus ventilation is limited (unless the ostium is very
large) and that the gas exchange of nitric oxide (NO) between the air in the maxillary
sinus and the nasal air does not contributor greatly to the overall NO concentration
(Fig. 8.39 ).