Numerical assessment of respiratory airway exposure risks to diesel exhaust particles

  • Jingliang Dong
  • Lin TianEmail author
  • Goodarz Ahmadi
Research Article


Exposure to ambient air pollution presents great adverse health risks to respiratory health, and assessing the respiratory exposure doses, especially in the human deep lung regions, remains difficult due to the sheer complexity of the process. To bridge this gap, an extended large-to-small conducting lung airway model was adopted in this study, which includes a broad scope containing bronchial airways up to the 15th generation. Accumulation mode particles in the size range of 100 nm to 3.0 μm representing major size spectrum of coarse diesel exhaust were released at the inlet of respiratory airway model, and both airflow and particle deposition characteristics were numerically investigated. The simulation results showed that the particle deposition in the respiratory airway is sensitive to the variation of inhalation flow rates. For inhalation exposure at lower breathing rate of 18 L/min, both deposited diffusive and inertia particles were very unevenly distributed in the lower respiratory airway. For inhalation exposure at higher breathing rate of 50 L/min, deposited diffusive and inertia particles were both scattered over the lower respiratory airway. In addition, high inhalation flow rate enabled inertia particles to be deposited further d ownstream of the airway with deposition hot spots observed in distal airways.


diesel exhaust respiratory airway occupational hygiene accumulation mode particles lobar deposition 



This study was funded by the National Natural Science Foundation of China (Grant Nos. 91643102 and 81700094) and Australian Research Council (Project ID: DP160101953 and DE180101138).


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Copyright information

© Tsinghua University Press 2019

Authors and Affiliations

  1. 1.School of EngineeringRMIT UniversityBundooraAustralia
  2. 2.Department of Aeronautical and Mechanical EngineeringClarkson UniversityPotsdamUSA

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