Numerical air conditioning performance assessment of nasal models with morphologic variations

A major functional role of the nasal cavity is air conditioning of the inspired environmental air to nearly alveolar conditions in order to protect the moist and warm alveolar lining where gas exchange takes place. It is well known that the morphological disparities among nasal passages can change airflow patterns to a great extent. However, this morphological variation effect on air conditioning performance remains unclear. This research aims to investigate the nasal air conditioning performance among nasal models with distinct vestibule phenotypes across subjects with normal healthy nasal anatomy and with symptoms of nasal disease. Numerical simulations considering humidified air with room temperature condition was conducted. Airflow pattern, heat and mass transfer between the inhaled airflow and the nasal mucosa were analysed and compared among selected nasal models. Results showed that the nasal air conditioning performance is closely related to nasal structures, and its morphological variations, especially in the nasal vestibule region, can induce up to 25% relative humidity, 3 °C temperature changes in anterior nasal region.