Experimental And Computational Modelling Of Air And Particle Flow In Lung Airway Bifurcations

 

Introduction

 

Understanding the flow of air and aerosol particles through the lung is essential to the success of pulmonary drug delivery. Much of the extensive work carried out to date has been based on simplified geometry for the bifurcating tree-like structure of the airways. The objective of this project is to characterise the flow of air and particles (such as droplets of inhaled medication, or pollutants) in a single anatomically realistic airway bifurcation, by both experimental and computational methods.

People

Dr. Nathan Quinlan, Kevin Heraty

 

Project

 

A realistic geometric model of a fourth generation airway bifurcation has been created from the Visible Human data set.

 

3D geometric model of a human tracheobronchial airway system, with the study region highlighted in red.

Comparative computational studies have been carried out for this model and a typical idealised bifurcation model. Our results reveal discrepancies between airflow in the idealised and realistic geometries, suggesting that it is important to model the physiological geometry accurately. Recently, we have used these techniques to investigate high-frequency oscillatory (HFO) ventilation, a form of fast, shallow mechanical ventilation in which air is provided to the patient at a rate of up to 10 breaths per second.

Computed velocity profiles in the idealised (left) and realistic (right) geometries. Colour denotes magnitude of velocity.

 

Sample Publications

 

Heraty KB, Laffey JG, Quinlan NJ, Fluid dynamics of gas exchange in high-frequency oscillatory ventilation: In Vitro Investigations in Idealized and Anatomically Realistic Airway Bifurcation Models, Annals of Biomedical Engineering 36(11):1856-1869, 2008.

Heraty KB, Quinlan NJ, Experimental modelling of airflow in airway bifurcations, Journal of Biomechanics 39:S595, 2006.