×

Numerical study of flow fields in an airway closure model. (English) Zbl 1241.76472

Summary: The liquid lining in small human airways can become unstable and form liquid plugs that close off the airways. Direct numerical simulations are carried out on an airway model to study this airway instability and the flow-induced stresses on the airway walls. The equations governing the fluid motion and the interfacial boundary conditions are solved using the finite-volume method coupled with the sharp interface method for the free surface. The dynamics of the closure process is simulated for a viscous Newtonian film with constant surface tension and a passive core gas phase. In addition, a special case is examined that considers the core dynamics so that comparisons can be made with the experiments of S. Bian et al. [J. Fluid Mech. 647, 391–402 (2010; Zbl 1189.76014)]. The computed flow fields and stress distributions are consistent with the experimental findings. Within the short time span of the closure process, there are large fluctuations in the wall shear stress. Furthermore, dramatic velocity changes in the film during closure indicate a steep normal stress gradient on the airway wall. The computational results show that the wall shear stress, normal stress and their gradients during closure can be high enough to injure airway epithelial cells.

MSC:

76Z05 Physiological flows
76D05 Navier-Stokes equations for incompressible viscous fluids
92C35 Physiological flow

Keywords:

multiphase flow

Citations:

Zbl 1189.76014
PDFBibTeX XMLCite
Full Text: DOI

References:

[1] DOI: 10.1017/S0022112003005573 · Zbl 1063.76557 · doi:10.1017/S0022112003005573
[2] DOI: 10.1017/S0022112083002451 · Zbl 0571.76046 · doi:10.1017/S0022112083002451
[3] DOI: 10.1017/S0022112092003227 · Zbl 0775.76054 · doi:10.1017/S0022112092003227
[4] DOI: 10.1063/1.3294573 · Zbl 1183.76234 · doi:10.1063/1.3294573
[5] Gunther, Am. J. Respir. Crit. Care Med. 153 pp 176– (1996) · doi:10.1164/ajrccm.153.1.8542113
[6] Guerin, Am. J. Respir. Crit. Care Med. 155 pp 1949– (1997) · doi:10.1164/ajrccm.155.6.9196101
[7] DOI: 10.1164/rccm.200405-575OC · doi:10.1164/rccm.200405-575OC
[8] Greaves, Handbook of Physiology. The Respiratory System: Mechanics of Breathing (1986)
[9] DOI: 10.1016/j.resp.2008.04.008 · doi:10.1016/j.resp.2008.04.008
[10] DOI: 10.1063/1.2938381 · Zbl 1182.76258 · doi:10.1063/1.2938381
[11] DOI: 10.1063/1.3183777 · Zbl 1183.76603 · doi:10.1063/1.3183777
[12] DOI: 10.1063/1.1948907 · Zbl 1187.76169 · doi:10.1063/1.1948907
[13] DOI: 10.1016/j.compfluid.2003.08.002 · Zbl 1100.76543 · doi:10.1016/j.compfluid.2003.08.002
[14] DOI: 10.1115/1.1798051 · doi:10.1115/1.1798051
[15] DOI: 10.1063/1.1862631 · Zbl 1187.76562 · doi:10.1063/1.1862631
[16] Ferziger, Computational Methods for Fluid Dynamics (1996) · doi:10.1007/978-3-642-97651-3
[17] tAAAAVeen, Am. J. Respir. Crit. Care Med. 161 pp 1902– (2000) · doi:10.1164/ajrccm.161.6.9906075
[18] DOI: 10.1088/0034-4885/71/3/036601 · doi:10.1088/0034-4885/71/3/036601
[19] Taskar, Am. J. Respir. Crit. Care Med. 155 pp 313– (1997) · doi:10.1164/ajrccm.155.1.9001330
[20] DOI: 10.1103/RevModPhys.69.865 · Zbl 1205.37092 · doi:10.1103/RevModPhys.69.865
[21] DOI: 10.1080/10407790500272095 · doi:10.1080/10407790500272095
[22] Shyy, Computational Modeling for Fluid Flow and Interfacial Transport (1994)
[23] DOI: 10.1017/S0022112084002226 · Zbl 0548.76032 · doi:10.1017/S0022112084002226
[24] DOI: 10.1007/s00134-005-2745-7 · doi:10.1007/s00134-005-2745-7
[25] DOI: 10.1136/adc.75.2.133 · doi:10.1136/adc.75.2.133
[26] DOI: 10.1183/09031936.95.08122139 · doi:10.1183/09031936.95.08122139
[27] Crystal, The Lung: Scientific Foundations (1997)
[28] DOI: 10.1016/0021-9991(77)90100-0 · Zbl 0403.76100 · doi:10.1016/0021-9991(77)90100-0
[29] DOI: 10.1017/S002211209700548X · Zbl 0892.76010 · doi:10.1017/S002211209700548X
[30] Cassidy, J. Appl. Physiol. 87 pp 415– (1999)
[31] Osher, Level Set Methods and Dynamic Implicit Surfaces (2003) · doi:10.1007/b98879
[32] DOI: 10.1063/1.2173969 · doi:10.1063/1.2173969
[33] Muscedere, Am. J. Respir. Crit. Care Med. 149 pp 1327– (1994) · doi:10.1164/ajrccm.149.5.8173774
[34] DOI: 10.1016/j.ijmultiphaseflow.2004.03.007 · Zbl 1136.76476 · doi:10.1016/j.ijmultiphaseflow.2004.03.007
[35] DOI: 10.1016/0034-5687(70)90015-0 · doi:10.1016/0034-5687(70)90015-0
[36] DOI: 10.1063/1.1582234 · doi:10.1063/1.1582234
[37] DOI: 10.1137/0143018 · Zbl 0511.76021 · doi:10.1137/0143018
[38] DOI: 10.1017/S0022112010000091 · Zbl 1189.76014 · doi:10.1017/S0022112010000091
[39] DOI: 10.1152/japplphysiol.01288.2003 · doi:10.1152/japplphysiol.01288.2003
[40] DOI: 10.1016/S0140-6736(98)09449-5 · doi:10.1016/S0140-6736(98)09449-5
[41] DOI: 10.1017/S0022112091000423 · Zbl 0738.76030 · doi:10.1017/S0022112091000423
[42] DOI: 10.1073/pnas.0610868104 · doi:10.1073/pnas.0610868104
[43] DOI: 10.1016/0021-9991(81)90145-5 · Zbl 0462.76020 · doi:10.1016/0021-9991(81)90145-5
[44] DOI: 10.1016/j.resp.2008.05.013 · doi:10.1016/j.resp.2008.05.013
[45] DOI: 10.1115/1.2835077 · doi:10.1115/1.2835077
[46] DOI: 10.1115/1.2895486 · doi:10.1115/1.2895486
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.