Temperature Profile in the Nasal Cavity

Abstract

The temperature increase of ambient air in the nasal airways can be compared with a logarithmic curve of the heating of air passing a heated tube. As the heating of air is important for water transport, the space between the nasal valve and the middle turbinate is of special functional importance. No correlation to the results of rhinomanometry was found.

From CT Scans to CFD Modelling – Fluid and Heat Transfer in a Realistic Human Nasal Cavity

“…The humidity profiles show trends similar to the experimental data of Keck et al (2000a) for the climatic air condition of 25 o C, 35% humidity. The humidity profile increases rapidly in the anterior nasal region, driven by the larger gradient difference and begins to converge to a steady value at a similar distance as the convergence of the temperature profile at x n = 0.5 from the inlet.…”

“…The critical flow rate at which the flow changes from laminar to the turbulent flow regime is difficult to succinctly define due to the complexity of the airway which has led to some debate concerning the type of airflow regime to implement for numerical simulations. Experimental studies by Swift and Proctor (1977) Keck et al, 2000a). This condition will be labelled "Normal Air Conditions".…”

“…Temperature values were related to nasal airway resistance data and followed a logarithmic curve. In addition, the same authors found that a high increase of humidity and temperature was found in the anterior nasal segment and that further increase of both parameters between the turbinate area and nasopharynx was less pronounced in spite of the longer distance (Keck et al, 2000a). A review paper by Wolf et al (2004) also discussed the air-conditioning characteristics of the human nose through results of in-vivo, in-vitro and computational simulations.…”

“…This may be attributed to the higher constant mucosal wall temperature used, since it was found by Lienar et al (2003) and Lindemann et al (2002) that the end-expiratory nasal mucosal wall temperature varied between 32.3°C and 34.7°C after exposure to 25°C inspired air. In other studies, the intranasal temperature values of 50 volunteers were measured after inspiration at different locations: nasal vestibule, nasal valve area, anterior to the head of the middle turbinate, and the nasopharynx (Keck et al, 2000b). Temperature values were related to nasal airway resistance data and followed a logarithmic curve.…”

Review of the upper airway, including olfaction, as mediator of symptoms.

“…Under most climatic conditions, inspired air is heated (to 37°C) and humidified (to near 100% relative humidity) in the upper airway (1). Filtration is accomplished mechanically by nasal vibrissae and by the process of impaction whereby large-diameterinspired particles collide with the turbinates and are subsequently cleared by the mucociliary apparatus.…”