Computational modeling methods for simulating obstructive human lung diseases
Introduction Obstructive lung diseases such as asthma & COPD are life-long inflammatory lung diseases. Their main characteristic is bronchoconstriction which alters the geometry and mechanical features of the airways. The development of computational models of the lungs taking into account details related to alterations of the lung geometry, tissue mechanical features and, changes of the airflow distribution inside the lung airways may allow an understanding of these diseases and improve diagnosis and assessment.
Methods Computational fluid dynamic (using FLUENT,ANSYS Inc) simulations using 3D lung airway models, reconstructed from CT scans and deformed appropriately (e.g. airway narrowing),were used to simulate bronchoconstriction. Specifically, we employed a Laplacian mesh contraction scheme for performing narrowing of the airway branches.
Results By inspecting Fig.1 we can conclude that air velocity increases in the contracted airway branches as compared to the non-contracted branch while the air pressure drops in the contracted version of the model. Specifically for a 40 % diameter reduction in a terminal airway, we observe a pressure drop of 48% with relevance to the lowest observed pressure value.
Conclusions Our computational model allows the study of the airflow characteristics in normal and obstructed lung airways
Stavros Nousias, Aris Lalos, Konstantinos Moustakas, Antonios Lalas, Dimitrios Kikidis, Konstantinos Votis, Dimitrios Tzovaras, Omar Usmani, Fan Chung "Computational modeling methods for simulating obstructive human lung diseases." European Respiratory Congress, 6-7 September, 2016