دورية أكاديمية
أعرض في EDS

Studying airflow structures in periodic cylindrical hills of human tracheal cartilaginous rings.

التفاصيل البيبلوغرافية
العنوان: Studying airflow structures in periodic cylindrical hills of human tracheal cartilaginous rings.
المؤلفون: Heidarinejad G; Department of Mechanical Engineering, Tarbiat Modares University, Tehran, Iran. Electronic address: gheidari@modares.ac.ir., Roozbahani MH; Department of Mechanical Engineering, Tarbiat Modares University, Tehran, Iran., Heidarinejad M; Department of Civil, Architectural, and Environmental Engineering, Illinois Institute of Technology, Chicago, IL, USA.
المصدر: Respiratory physiology & neurobiology [Respir Physiol Neurobiol] 2019 Aug; Vol. 266, pp. 103-114. Date of Electronic Publication: 2019 Apr 24.
نوع المنشور: Journal Article
اللغة: English
بيانات الدورية: Publisher: Elsevier Science Country of Publication: Netherlands NLM ID: 101140022 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1878-1519 (Electronic) Linking ISSN: 15699048 NLM ISO Abbreviation: Respir Physiol Neurobiol Subsets: MEDLINE
أسماء مطبوعة: Original Publication: Amsterdam ; New York : Elsevier Science, c2002-
مواضيع طبية MeSH: Models, Anatomic* , Models, Biological* , Respiratory Physiological Phenomena*, Cartilage/*anatomy & histology , Trachea/*anatomy & histology, Computer Simulation ; Humans
مستخلص: The objective of this study is to assess tracheobronchial flow features with the cartilaginous rings during a light exercising. Tracheobronchial is part of human's body airway system that carries oxygen-rich air to human's lungs as well as takes carbon dioxide out of the human's lungs. Consequently, evaluation of the flow structures in tracheobronchial is important to support diagnosis of tracheal disorders. Computational Fluid Dynamics (CFD) allows evaluating effectiveness of tracheal cartilage rings in human body under different configurations. This study utilizes Large Eddy Simulation (LES) to model an anatomically-based human large conducting airway model with and without cartilaginous rings at the breathing conditions at Reynolds number of 5,176 in trachea region. It is observed that small recirculating areas shaped between rings cavities. While these recirculating areas are decaying, similar to periodic 2D-hills, the cartilaginous rings contribute to the construction of a vortical flow structure in the main flow. The separated vortically-shaped zone creates a wake in the flow and passes inside of the next ring cavity and disturb its boundary layer. At last, the small recirculation flow impinges onto tracheal wall. The outcome of this impinge flow is a latitudinal rotating flow perpendicular to the main flow in a cavity between the two cartilaginous rings crest which appear and disappear within a hundredth of a second. Kelvin-Helmholtz instability is observed in trachea caused by shear flow created behind of interaction between these flow structures near to tracheal wavy wall and main flow. A comparison of the results between a smooth wall model named simplified model and a rough wall model named modified model shows that these structures do not exist in simplified model, which is common in modeling tracheobronchial flow. This study proposes to consider macro surface roughness to account for the separating and rotating instantaneous flow structures. Finally, solving trachea airflow with its cartilages can become one of major issues in measuring the validity and capability of solving flow in developing types of sub-grid scale models as a turbulence studies benchmark.
(Copyright © 2019 Elsevier B.V. All rights reserved.)
فهرسة مساهمة: Keywords: Human airways; Kelvin-Helmholtz instability; Large Eddy Simulation; Tracheobronchial flow; Vortical flow structur
تواريخ الأحداث: Date Created: 20190428 Date Completed: 20200403 Latest Revision: 20200403
رمز التحديث: 20231215
DOI: 10.1016/j.resp.2019.04.012
PMID: 31028849
قاعدة البيانات: MEDLINE
الوصف
تدمد:1878-1519
DOI:10.1016/j.resp.2019.04.012