Numerical simulations of high-frequency respiratory flows in 2D and 3D lung bifurcation models

作者：Parameswaran Siva; Chen Zixi; Parameswaran Shamini; Hu Yingying; He Zhaoming; Raj Rishi

来源：International Journal of Computational Methods in Engineering Science and Mechanics, 2014, 15(4): 337-344.

DOI：10.1080/15502287.2014.904454

• 3-d numerical models
• Gas transport
• Gas transportation
• HFOV
• High frequency HF
• Oxygen concentrations
• Wall shear stress
• Womersley numbers

To better understand the human pulmonary system and optimize the high-frequency oscillatory ventilation (HFOV) design, numerical simulations were conducted under normal breathing frequency and HFOV condition using a CFD code Ansys Fluent and its user-defined C programs. 2D and 3D double bifurcating lung models were created, and the geometry corresponds to fifth to seventh generations of airways with the dimensions based on the Weibel's pulmonary model. Computations were carried out for different Reynolds numbers (Re = 400 and 1000) and Womersley numbers (α; = 4 and 16) to study the air flow fields, gas transportation, and wall shear stresses in the lung airways. Flow structure was compared with experimental results. Both 2D and 3D numerical models successfully reproduced many results observed in the experiment. The oxygen concentration distribution in the lung model was investigated to analyze the influence of flow oscillation on gas transport inside the lung model.

• 出版日期2014
• 单位University of Michigan, Ann Arbor