Combined effects of the nasal cycle and septal deviation on the relative humidity in the nasal cavity during inspiration

In the presence of nasal septal deviation, the airflow can be skewed to the convex side of the airway. Asymmetry of the airflow partition can be aggravated if the decongestion phase of the nasal cycle occurs on the same side. This numerical study investigates the variation in the airflow partition over time during inspiration and the corresponding changes in relative humidity when septal deviation is combined with the nasal cycle. In the nasal cavities with a decongested convex side, the variation in the airflow partition ratio observed over time was larger than that in the nasal cavities not influenced by the nasal cycle. In addition, the decrease in the relative humidity of the convex side was larger, resulting in a relative humidity of as low as 76.3 %. Therefore, the convex side of the deviated cavity was more prone to nasal dryness under the influence of the nasal cycle.