真实人体上呼吸道规范模型流场PIV实验研究

PIV experiment on flow fields of the real human upper respiratory tract gauge model

目的研究上呼吸道模型内气流组织形式,深入认识上呼吸道内气流运动特性,为分析气溶胶在人体上呼吸道内的扩散、转捩以及沉积模式提供科学依据。方法采用粒子图像测速(particle image velocimetry,PIV)技术对真实人体上呼吸道模型内流场进行了实验研究,并针对口腔、咽腔和气管等不同位置对气流状态进行了分析。结果气流在舌苔上部和口腔中部速度较高,到咽部时,由于截面积的变小而导致气流速度增大,在声门处气流速度达到最大(10.24 m/s),且在气管内呈前高后低分布;而在涡量分布方面,气流在声门部位产生强烈的喷射,致使气管内部速度梯度增加,在声门的前后壁面形成两个涡量集中区,并导致气管前壁面的涡量值要明显高于后壁面。结论 PIV是研究人体上呼吸道内气流组织形式的一种有效方法,对于探索有毒气溶胶对人体的危害和吸入药物气溶胶的治疗效果以及研究呼吸系统的发病机理有着重要的意义。

Objective To investigate the airflow distribution mode in human upper respiratory tract model for un- derstanding the characteristics of the airflow in human upper respiratory tract, and provide scientific basis for ana- lyzing the diffusion, transition and deposition patterns of aerosol in human upper respiratory tract. Methods PIV （ particle image velocimetry）technology was adopted to study flow fields of the real human upper respiratory tract model. The airflow state in oral cavity, pharynx and trachea was analyzed. Results The flow velocity was rela- tively high at the upper tongue coating and in the middle of the oral cavity; when the airflow reached the pharynx, the velocity was increased rapidly due to the reduction of sectional area; the maximum velocity （10.24 m/s） ap- peared in the glottis, and the velocity in the anterior wall was higher than that in the posterior wall of the trachea; as the airflow injected at the glottis, the velocity gradient was increased, and the vorticity was concentrated at the anterior and posterior wall of the glottis, resulting in a significantly higher vorticity value at anterior wall of the tra- chea than that at the posterior wall. Conclusions PIV technology is an effective way to investigate the airflow dis- tribution mode in human upper respiratory tract, and it is of great importance for exploring the harm of toxic aero- sol to human body and the therapeutic effect of inhalation drug aerosol, as well as for researching the pathogene- sis of respiratory system.