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Effects of the ambient temperature on the airflow across a Caucasian nasal cavity
Author(s) -
Burgos M.A.,
SanmiguelRojas E.,
MartínAlcántara A.,
HidalgoMartínez M.
Publication year - 2014
Publication title -
international journal for numerical methods in biomedical engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.741
H-Index - 63
eISSN - 2040-7947
pISSN - 2040-7939
DOI - 10.1002/cnm.2616
Subject(s) - airflow , ambient pressure , mechanics , dimensionless quantity , nasal cavity , pressure drop , materials science , heat exchanger , laminar flow , thermodynamics , anatomy , physics , medicine
SUMMARY We analyse the effects of the air ambient temperature on the airflow across a Caucasian nasal cavity under different ambient temperatures using CFD simulations. A three‐dimensional nasal model was constructed from high‐resolution computed tomography images for a nasal cavity from a Caucasian male adult. An exhaustive parametric study was performed to analyse the laminar‐compressible flow driven by two different pressure drops between the nostrils and the nasopharynx, which induced calm breathing flow rates ࣈ 5.7 L/min and ࣈ 11.3 L/min. The inlet air temperature covered the range − 10 o C ⩽ T o ⩽ 50 o C . We observed that, keeping constant the wall temperature of the nasal cavity at 37 o C , the ambient temperature affects mainly the airflow velocity into the valve region. Surprisingly, we found an excellent linear relationship between the ambient temperature and the air average temperature reached at different cross sections, independently of the pressure drop applied. Finally, we have also observed that the spatial evolution of the mean temperature data along the nasal cavity can be collapsed for all ambient temperatures analysed with the introduction of suitable dimensionless variables, and this evolution can be modelled with the help of hyperbolic functions, which are based on the heat exchanger theory. Copyright © 2013 John Wiley & Sons, Ltd.