人体上呼吸道内压力循环变动的流场特性仿真研究

Simulation of flow field characteristics of cyclic variation of human upper respiratory tract

目的 探索循环呼吸条件下人体上呼吸道内压力分布和变动情况。 方法 基于CT扫描图像建立口腔-二级支气管模型，仿真研究呼吸流量为60 L/min条件下，循环呼吸过程中模型各部位的压力变化及最大瞬时吸气或呼气时刻的压力分布。结果 呼吸流量增大时，上呼吸道腔体内压力差也随之增大；在咽部、喉部、气管分岔处这些具有特殊结构的部位呈现压力梯度的变化，集中在会厌下缘至气管处及气管分岔处。 结论 呼吸道解剖结构形态与气流运动相应的力的分布和变化，交互作用并共同影响呼吸过程。压力循环变动的流场特性可为探讨气溶胶沉积以及一些呼吸道疾病的发生和治疗提供依据。

Objective To explore the distribution and changes of the upper respiratory tract pressure in the human body under circulatory respiration conditions.Methods An oral-secondary bronchus model was established based on CT images.The pressure distribution at various parts of the model during circulatory respiration and the pressure distribution at the moment of maximum inspiration or expiration were simulated under a respiratory flow of 60 L/min.Results The pressure difference in the upper respiratory tract increased with the respiratory flow.Some positions with special structures,such as pharynx,larynx,trachea,etc.,showed pressure gradient changes,especially between edge of epiglottis to the trachea and upon the bifurcation point of tracheal.Conclusions The air flow motion,including pressure distribution and variation,is related to the anatomy morphological structure of the respiratory tract,and they interactively influence the respiration process.The flow field characteristics of pressure cyclic variation can provide basis for exploring the aerosol deposition and the occurrence and treatment of some respiratory tract diseases.