Computational fluid dynamics simulation of air flow in the human symmetrical six-generation bifurcation bronchial tree model

Abstract

The present study aims to reveal the velocity and pressure distributions of air flow in the human symmetrical six-generation bifurcation bronchial tree model, to determine the influences of homothetic ratio, the angle of branching, and the branching plane rotation angle on the air flow. The 3D bronchial tree model is built up using SolidWorks based on optimal parameters from the references at first. And then it is transferred into ANSYS, one computational fluid dynamics software, to simulate the air flow and get the velocity and pressure distributions. Similarly, three different models are established by varying homothetic ratio, the angle of branching, and the branching plane rotation angle. Their impacts on the air flow are clarified through comparing the results. It is found the velocity and pressure distributions are symmetical genrally, but they start uneven from the fourth generation bronchus. The velocities in the inner and inferior bronchi are smaller than in the outer and superior ones. The pressure drop will decrease with the homothetic ratio, but it also increases the tree volume. The variations of the branching angle and the branching plane rotation angle will increase the pressure drop. The simulation results can reveal the air flow patterns in the models, and work as the benchmark for the future ventilation assessment of realistic human lung. © Springer Science+Business Media Dordrecht 2014.