Deposition of droplets from the trachea or bronchus in the respiratory tract during exhalation: A steady-state numerical investigation
Deposition of droplets from the trachea or bronchus in the respiratory tract during exhalation: A steady-state numerical investigation
复制标题
呼气时气管或支气管中液滴在呼吸道中的沉积：稳态数值研究
DOI：
10.1080/02786826.2020.1772459
复制
发表时间：
2020-08-02
影响因子：
5.2
通讯作者：
Li, Yuguo
中科院分区：
文献类型：
--
作者：
Guo, Yong;Wei, Jianjian;Li, Yuguo
呼吸道飞沫是源自呼吸道的生物气溶胶。了解它们在呼气过程中的沉积特性将有助于理解大的呼吸道飞沫的来源及其在呼吸道传染病传播中的重要性。在这项研究中，计算流体动力学是用来模拟的运动和沉积液滴释放的气管或支气管在一个现实的重建人类呼吸道。研究了气流结构和液滴生成位置对液滴沉积的影响，并对直径在1 ~ 50 μ m之间的液滴进行了检测。液滴的沉积主要受液滴直径和呼气流速的影响。从气管或支气管释放的可以逃逸到环境中的液滴的数量随着流速的增加而减少。当流速低（10 L/min）时，在下呼吸系统中产生的液滴能够逃逸到空气中的临界直径约为12 μ m，但是当流速中等（30至60 L/min）或大（90 L/min）时，该直径约为5 μ m。喉部是小于临界直径的液滴的主要沉积部位，而气管和支气管是更重要的位置，其导致较大液滴的沉积。这项研究表明，下呼吸道是细小飞沫的重要来源（
Respiratory droplets are bioaerosols that originate from the respiratory tract. Knowing their deposition characteristics during exhalation would facilitate the understanding of the source of large respiratory droplets and their importance in the spread of respiratory infectious diseases. In this study, computational fluid dynamics is used to simulate the motion and deposition of droplets released from either trachea or bronchi in a realistic reconstruction of the human respiratory tract. Influences of airflow structures and locations of droplet generation on droplet deposition are studied, and droplets with diameters between 1 and 50 mu m are examined. The deposition of droplets is found to be influenced mainly by the droplet diameter and the flow rate of exhalation. The number of droplets released from the trachea or bronchi that can escape into the environment decreases as the flow rate increases. When the flow rate is low (10 L/min), the critical diameter of droplets generated in the lower respiratory system that can escape into the air is approximately 12 mu m, but this diameter is approximately 5 mu m when the flow rate is medium (30 to 60 L/min) or large (90 L/min). The larynx is the dominant site of deposition for droplets smaller than the critical diameter, while trachea and bronchus are more important locations that account for the deposition of larger droplets. This study indicates that the lower respiratory tract is an important source of fine droplets (