Abstract：
This paper presents a numerical investigation to understand the transport and deposition of sprays emitted by an impinging-jet inhaler in the human respiratory tract under different inhalation flow rates. An injection model is used for the numerical simulations considering the spreading angles of the spray in the two directions, which are measured from experiments. The model parameter is adjusted to match the mean droplet size measured in the previous experiment. A time-varying sinusoidal inhalation flow rate is utilized as airflow conditions, which is closer to the actual situation when using an inhaler. The results demonstrate that the inhalation airflow rate significantly affects the spray\'s transport behavior and deposition results in the respiratory tract. Both excessively high and low inhalation flow rates lead to an increase in deposition in the mouth-throat. A moderate inhalation flow rate reduces throat deposition while maximizing lung deposition. Higher inhalation flow rates enable faster delivery of the droplets to the lungs, whereas lower inhalation flow rates achieve a more uniform deposition over time in the lungs. The amount of deposition in different parts of the lung lobes follows a fixed order. This study provides valuable insights for optimizing the inhalation flow rate conditions of the impinging-jet inhaler for clinical applications.
摘要：
本文进行了数值研究，以了解在不同的吸入流量下，撞击式吸入器在人体呼吸道中喷出的喷雾的传输和沉积。考虑喷雾在两个方向上的扩散角，使用喷射模型进行数值模拟。从实验中测量。调整模型参数以匹配先前实验中测量的平均液滴尺寸。随时间变化的正弦吸入流速被用作气流条件，这更接近使用吸入器时的实际情况。结果表明，吸入气流速率显着影响喷雾的运输行为和呼吸道中的沉积结果。过高和过低的吸入流速都会导致口腔咽喉中的沉积增加。适度的吸入流速减少咽喉沉积,同时最大化肺沉积。更高的吸入流速可以更快地将液滴输送到肺部，而较低的吸入流速在肺中随着时间的推移实现更均匀的沉积。肺叶不同部分的沉积量遵循固定的顺序。本研究为临床应用优化冲击射流吸入器的吸入流量条件提供了有价值的见解。
