Academic Journal

Flow characteristics in a nasal to tracheo-bronchial airway using a scale resolving simulation.

Λεπτομέρειες βιβλιογραφικής εγγραφής
Τίτλος: Flow characteristics in a nasal to tracheo-bronchial airway using a scale resolving simulation.
Συγγραφείς: Warfield-McAlpine P; Department of Mechanical Manufacturing Mechatronic Engineering, RMIT University, PO Box 71, Bundoora, 3083, Australia., Emmerling J; School of Engineering, Deakin University, Geelong, Victoria 3217, Australia., Fletcher DF; School of Chemical and Biomolecular Engineering, The University of Sydney, NSW 2006, Australia., Inthavong K; Department of Mechanical Manufacturing Mechatronic Engineering, RMIT University, PO Box 71, Bundoora, 3083, Australia. Electronic address: kiao.inthavong@rmit.edu.au.
Πηγή: Computers in biology and medicine [Comput Biol Med] 2026 Aug 15; Vol. 213, pp. 111805. Date of Electronic Publication: 2026 Jun 16.
Τύπος έκδοσης: Journal Article
Γλώσσα: English
Στοιχεία περιοδικού: Publisher: Elsevier Country of Publication: United States NLM ID: 1250250 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1879-0534 (Electronic) Linking ISSN: 00104825 NLM ISO Abbreviation: Comput Biol Med Subsets: MEDLINE
Imprint Name(s): Publication: New York : Elsevier
Original Publication: New York, Pergamon Press.
Ιατρικοί όροι (MeSH): Bronchi*/physiology , Bronchi*/diagnostic imaging , Trachea*/physiology , Trachea*/diagnostic imaging , Nasal Cavity*/physiology , Nasal Cavity*/diagnostic imaging , Models, Biological* , Computer Simulation*, Humans
Περίληψη: Background and Objective Airflow dynamics are fundamental to understanding respiratory function, yet the complexity of flow regimes within the nasal and tracheo-bronchial pathways remains poorly characterised. This study employed a patient-specific respiratory model, extending from the nasal cavity to the 7th-generation bronchioles, to investigate airflow characteristics at a steady inhalation rate of 30 L/min. Methods A hybrid Stress-Blended Eddy Simulation (SBES) model was used to capture unsteady flow structures, while Dynamic Mode Decomposition (DMD) and spectral analysis were applied to identify dominant flow dynamics. The computational model, derived from CT scans, used a poly-hexcore mesh with ∼ 30 million cells. This study provides a unified, scale-resolving characterisation of airflow from the nasal cavity to distal bronchioles, linking flow behaviour across regions using modal and spectral diagnostics. Results The results revealed laminar-dominant flow in the nasal cavity, with velocities increasing to 6.2-8.4 m/s, and high-velocity jet formation in the laryngeal region with peak velocities of up to 14.9 m/s. This region exhibited enhanced unsteadiness and strong oscillatory behaviour, with resolved turbulence kinetic energy reaching up to 35 m2/s2. Downstream, flow progressively transitioned toward laminar-dominant conditions in distal bronchioles, with reduced velocity (0.8-3.6 m/s) and low energy content. Coherent structures identified via the q-criterion and DMD highlighted regions of energy redistribution and high-frequency oscillations. Flow partitioning between left and right bronchial branches showed asymmetry, with total distributions of 44.65% and 55.35%, respectively. Conclusions This study provides a unified characterisation of airflow dynamics across the upper and lower airways, identifying key regions of enhanced unsteadiness and downstream energy dissipation, with implications for respiratory modelling and device design.
(Crown Copyright © 2026. Published by Elsevier Ltd. All rights reserved.)
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Contributed Indexing: Keywords: Bronchial; CFD; Flow characterisation; LES; Nasal; Respiratory
Entry Date(s): Date Created: 20260616 Date Completed: 20260722 Latest Revision: 20260722
Update Code: 20260723
DOI: 10.1016/j.compbiomed.2026.111805
PMID: 42302458
Βάση Δεδομένων: MEDLINE
Περιγραφή
ISSN:1879-0534
DOI:10.1016/j.compbiomed.2026.111805