ARUP; ISBN: 978-0-9562121-5-3 - CMBBE 2012 - Cardiff University

cavity functions, nasal cavity wall model was developed by us. Although latent heat
effect was not considered in our previous model [3], latent heat is deprived due to
transition of water through the mucous membrane to air. It influences temperature of
inhaled air in the nasal cavity. Therefore, We developed the nasal cavity wall model for
heat and humidity exchange considering latent heat. We simulated airflow of nasal
cavity included maxillary sinus using developed model. Furthermore, we examined it
comparing temperature and relative humidity in the nasal cavity with the measurement
result. Near nasal valve, unrealistic high temperature distribution was simulated using
our previous model. In developed model, Excessive high temperature region was
disappeared. And, the result using developed model illustrated good agreement with the
measurement results. Consequently, the developed model can simulate heat and
humidity exchange in the nasal cavity.
3. Nasal Cavity Model
Nasal cavity wall is consisted of mucus membrane, layer of blood vessel and etc [4].
The nasal cavity wall surface is covered by mucus membrane. Temperature and
humidity of inhaled air is adjusted by heat and humidity exchange through mucus
membrane. Our previous model showed the temperature and humidity distribution in
the nasal cavity [3]. However, latent heat effect was not considered in our previous
model. Latent heat is deprived due to transition of water through the mucus membrane
to air. It influences temperature of inhaled air in the nasal cavity. Therefore, the nasal
cavity wall model that was considered latent heat was developed.
3.1 Nasal Cavity Wall Model for Temperature exchange
Fig.1 Nasal Cavity Wall Model for Heat exchange
TS !TO Qmemb = Kmemb Q total = Q memb +Q latent = K memb
! memb
(1)
Q latent = LW bl (2)
T S !T O
! memb
+ LW bl
Figure 1 illustrates the nasal cavity wall model for temperature exchange. Heat is
translated between airside and organ side via mucus membrane, where TS is temperature
on the surface on the membrane. TO is temperature on the organ side. Kmemb is thermal
conductance of the membrane. Qmemb is defined by equation (1). When TS is lower than
TO, the air in the nasal cavity is heated by heat supply from the organ side. When TS is
higher than TO, The air in the nasal cavity is cooled by deprive heat from the organ side.
Qlatent is defined by equation (2), where L is the latent heat that calculated by
(3)