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Biological Systems and Biomimetics
Published in Efstathios E. Michaelides, Clayton T. Crowe, John D. Schwarzkopf, Multiphase Flow Handbook, 2016
Efstathios E. Michaelides, Clayton T. Crowe, John D. Schwarzkopf
single graph for each studied nasal passage. However, the intersubject variability between the nasal passages signi cantly a ects the ber deposition. As expected, the anatomy of the nasal cavity markedly a ects the deposition rates of bers as well as of spherical particles. Variations in the anatomy of the nasal passages are associated with the changes in the pressure drop for a given ow rate. e higher pressure drop in the nasal cavity is due to small Effective cross section and leads to an increase in ber deposition. e experimental data of Su and Cheng (2005) for ber deposition are also presented in Figure 16.34 for comparison. is gure shows that the experimental DF for the nasal passage used by Su and Cheng is markedly higher than the simulated results. at again shows that the IP cannot reduce the intersubject variations and the di erences among the DF values for di erent nasal cavities still remain. Figure 16.35 shows the spatial deposition pattern of bers for case A for a ow rate of Q = 5 L/min. It is seen that as the IP increases, the DF increases. is gure also shows that as the IP increases, the regional deposition pattern also changes to an extent. In particular, bers with high IP deposit heavily in certain region of the nose where sharp changes in ow direction occur. For nasal passage A, Figure 16.36 compares the DF predicted by the ber model (solving the coupled translational and rotational equations of motions of ellipsoids) with the HL model described in Section 16.1.4.4.1. It is seen that the HL model follows the trend of the ber simulation results. e HL model results are, however, somewhat scattered compared with the ber model and the corresponding simulation results do not collapse onto a single curve. In addition, for the range of the parameter in this gure, the HL model overestimates the DF by factor of about 2. While the HL model is a much simpler model and reduces the computational time, it does not account for the actual physics of the ber motion in the air ow and does not provide accurate estimates for the ber DFs. 16.1.6 Conclusions In this chapter, a review of recent literature on respiratory ow and deposition is presented. Fundamentals of particles and ber transport and deposition are outlined and particular attention is given to recent advances in computational modeling of nano- and microparticles as well as ber transport and deposition in human upper airways. Sample results on transport and deposition processes in nasal cavity, throat, larynx, and pharynx, as well as trachea and main le and right bronchus, are presented. Both nasal and oral breathing conditions are discussed. An example of Effects of septoplasty surgery on particle deposition in human nasal passage is presented. e particle transport and deposition for pre- and postmaxillary sinus endoscopic surgery are also discussed. e Effects of the surrounding environment including the facial features, as well as turbulent air ow
In-silico investigation of airflow and micro-particle deposition in human nasal airway pre- and post-virtual transnasal sphenoidotomy surgery
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2022
Khashayar Moshksayan, Hojat Bahmanzadeh, Mohammad Faramarzi, Sasan Sadrizadeh, Goodarz Ahmadi, Omid Abouali
Particle deposition was also investigated by many studies of the human nasal airway using CFD models (Li et al. 2012). Flow pattern alterations resulting from septoplasty surgery were investigated in several studies and demonstrated considerable changes in nano- and micro-particle deposition patterns within the nasal cavity (Garcia et al. 2010). The deposition patterns of fiber particles of different shapes, such as ellipsoidal particles (Abolhassantash et al. 2020; Kiasadegh et al. 2020), were also simulated in human nasal airway (Shanley et al. 2018). Calmet et al. simulated the aerosol drug delivery to the nose from nasopharynx during exhalation in the rest and exercise conditions to assess the curative effect of this method for Eosinophilic Chronic Rhinosinusitis patients with asthma (Calmet et al. 2019).
A numerical study of flow field and particle deposition in nasal channels with deviant geometry
Published in Engineering Applications of Computational Fluid Mechanics, 2021
Eveline L. Thune, Pawel Kosinski, Boris V. Balakin, Sergey Alyaev
Finally, it is of interest to compare geometry 1 and 2 to see how the operational removal of an obstruction influences particle deposition. During septoplasty or turbinate reduction surgery, the nasal mucosa are normally reduced, thus reducing the area to which particles can stick. Expectedly, geometry 2 shows a lower deposition efficiency compared to the pre-operative model of geometry 1. The reduced depositional efficiency might be among the causes of sensitive changes result in the ENS syndrome.