G0500402 A Numerical Study of Air and Particle Flow in a tracheobronchial model based on a CT image

Abstract

Inhalants, such as bronchodilators, are often used to treat asthma. Computer fluid dynamics (CFD) can be applied to quantitatively evaluate the transport and deposition of medicinal particulates in the respiratory tract. In this study, the oral cavity, the pharynx, the larynx, the trachea and intra-thoracic central airways of up to 7 generations were modeled based on a CT image of a human lung. There are a total of 42 peripheral airways. Air flow and particle motion were simulated by Large-Eddy Simulation (LES) in a CFD software OpenFOAM ver 2.3.1. The inflow condition assumed such a respiratory pattern when an inhaler is used, i.e., inhalation followed by breath-holding, and the air flow and particle motion during inhalation were analyzed. The flow velocity reached maximum at the throat. Difference in particle size affected the transport and deposition of the particles in the respiratory tract, and many particles deposited in the branches of the respiratory tract and the throat.