The way the wind blows: implications of modeling nasal airflow.

Nasal airflow is important for the many physiological functions of the nose, which include the warming and humidifying of inspired air; the filtration of airborne pollutants; and the sense of smell and nasal pungency. Until recently, airflow properties in the nose could only be understood using qualitative in vitro models of humans or in vivo studies in rodents. Recent advances in constructing three-dimensional geometric models of human nasal passages from CT scans, coupled with computational fluid dynamic modeling, has been a valuable tool for quantifying airflow and transport of gases, heat, particles, and aerosols in the human nose. Additionally, these techniques hold significant promise for evaluating and predicting the impact and successful remediation of a variety of clinical conditions on olfaction and nasal patency and setting guidelines for safe levels of exposure to inhaled materials.