Table of Contents
Physics Research International
Volume 2012 (2012), Article ID 142756, 11 pages
http://dx.doi.org/10.1155/2012/142756
Research Article

A Computer Model for the Simulation of Nonspherical Particle Dynamics in the Human Respiratory Tract

Brunnleitenweg 41, A-5061 Elsbethen, Salzburg, Austria

Received 29 April 2011; Accepted 21 October 2011

Academic Editor: Anil Chourasia

Copyright © 2012 Robert Sturm. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

In the study presented here deposition of spheres and nonspherical particles with various aspect ratios (0.01–100) in the human respiratory tract was theoretically modeled. Shape of the nonspherical particles was considered by the application of the latest aerodynamic diameter concepts. Particle deposition was predicted by using a stochastic model of the lung geometry and simulating particle transport trajectories according to the random-walk algorithm. Concerning fibers total deposition is significantly enhanced with respect to that of spheres for μm-sized particles, whereby at normal breathing conditions peripheral lung compartments serve as primary deposition targets. In the case of oblate disks, total deposition becomes mostly remarkable for submicron particles, with the bronchioli and alveoli being targeted to a high extent. Enhancement of the aerodynamic diameter and/or flow rate generally causes a displacement of deposition maxima from peripheral to more proximal lung regions. From these findings, it can be concluded that these particle classes may represent tremendous occupational hazards, especially if they are attached with radioactive elements or heavy metals.