Numerical simulation of ozone transport and uptake in asymmetrically-branched airways of the respiratory tract

Banafsheh Keshavarzi, James Ultman, Ali Borhan

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

The pattern of lung injury induced by the inhalation of reactive gases such as O3, a ubiquitous air pollutant, is believed to depend on the dose delivered to different tissues in the respiratory tract. To test this hypothesis, numerical simulations of ozone transport and uptake in anatomically-correct geometries of the conductive airways of a Rhesus monkey were conducted. The airway geometry was created using three-dimensional reconstruction of the tracheobronchial tree from MRI images of the lung, and an unstructured volume mesh was generated for the first few generations of the resulting branched structure. Three-dimensional numerical solutions of the Navier-Stokes, continuity, and species convection-diffusion equations subject to a surface reaction wall condition were subsequently obtained for steady inspiratory and expiratory flows at physiologically relevant Reynolds number ranging from 100 to 500. An effective rate constant for the surface reaction was formulated based on a quasi-steady diffusion-reaction analysis in the epithelial lining fluid. The total rate of O3 uptake within each generation was determined, and hot spots of O3 flux on the airway walls were identified. Spikes in O3 flux appeared downstream of the first bifurcation. Results of the three-dimensional simulations for O3 uptake along a single asymmetrically-branched airway path were also compared to the predictions of an axisymmetric single-path model. This is an abstract of a paper presented at the AIChE Annual Meeting (San Francisco, CA 11/12-17/2006).

Original languageEnglish (US)
Title of host publication2006 AIChE Annual Meeting
StatePublished - 2006
Event2006 AIChE Annual Meeting - San Francisco, CA, United States
Duration: Nov 12 2006Nov 17 2006

Other

Other2006 AIChE Annual Meeting
CountryUnited States
CitySan Francisco, CA
Period11/12/0611/17/06

Fingerprint

Ozone
Respiratory System
Convection
Air Pollutants
San Francisco
Computer simulation
Surface reactions
Lung Injury
Macaca mulatta
Inhalation
Gases
Fluxes
Lung
Geometry
Linings
Magnetic resonance imaging
Rate constants
Reynolds number
Tissue
Fluids

All Science Journal Classification (ASJC) codes

  • Biotechnology
  • Chemical Engineering(all)
  • Bioengineering
  • Safety, Risk, Reliability and Quality

Cite this

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abstract = "The pattern of lung injury induced by the inhalation of reactive gases such as O3, a ubiquitous air pollutant, is believed to depend on the dose delivered to different tissues in the respiratory tract. To test this hypothesis, numerical simulations of ozone transport and uptake in anatomically-correct geometries of the conductive airways of a Rhesus monkey were conducted. The airway geometry was created using three-dimensional reconstruction of the tracheobronchial tree from MRI images of the lung, and an unstructured volume mesh was generated for the first few generations of the resulting branched structure. Three-dimensional numerical solutions of the Navier-Stokes, continuity, and species convection-diffusion equations subject to a surface reaction wall condition were subsequently obtained for steady inspiratory and expiratory flows at physiologically relevant Reynolds number ranging from 100 to 500. An effective rate constant for the surface reaction was formulated based on a quasi-steady diffusion-reaction analysis in the epithelial lining fluid. The total rate of O3 uptake within each generation was determined, and hot spots of O3 flux on the airway walls were identified. Spikes in O3 flux appeared downstream of the first bifurcation. Results of the three-dimensional simulations for O3 uptake along a single asymmetrically-branched airway path were also compared to the predictions of an axisymmetric single-path model. This is an abstract of a paper presented at the AIChE Annual Meeting (San Francisco, CA 11/12-17/2006).",
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Keshavarzi, B, Ultman, J & Borhan, A 2006, Numerical simulation of ozone transport and uptake in asymmetrically-branched airways of the respiratory tract. in 2006 AIChE Annual Meeting. 2006 AIChE Annual Meeting, San Francisco, CA, United States, 11/12/06.

Numerical simulation of ozone transport and uptake in asymmetrically-branched airways of the respiratory tract. / Keshavarzi, Banafsheh; Ultman, James; Borhan, Ali.

2006 AIChE Annual Meeting. 2006.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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