分析人体上呼吸道内流固耦合现象,深入认识上呼吸道内气流运动特性,对于研究气溶胶在人体上呼吸道内的扩散、转捩及沉积模式具有重要作用。运用流固耦合力学数值仿真方法,在呼吸流量为30 L/min的状态下,对人体上呼吸道内稳态气流运动特性进行数值模拟,系统分析流固耦合作用下上呼吸道壁面的形变特点、壁面剪切应力分布以及呼吸道内的气流运动特点。结果表明:在低强度稳态呼吸模式下,人体上呼吸道整体向后运动,三级支气管位移最大为4.99 mm,气管前壁面受到拉伸,后壁面受到压缩;口喉模型中受到的壁面剪应力较大,最大处可达30.34 Pa,气管支气管受到的壁面剪切应力较小;气流速度在声门处达到最大值7.85 m/s,在咽部外壁、气管外壁发生分离现象,气流在气管内壁形成局部高速区,支气管内气流在分叉处分离,靠近支气管内壁速度较高。
Research the effect of fluid-solid coupling on human upper respiratory tract can lead to deep understanding of the characteristics of the airflow in human upper respiratory tract and plays a very important role in analyzing the diffusion,transition and deposition patterns of aerosol in human upper respiratory tract.The numerical simulation of fluid-solid interaction mechanics was applied to simulate airflow movement in human upper respiratory tract model in the conditions of low intensive respiratory patterns(respiratory flow is 30 L/min),the shape variation and shear stress distribution in human upper respiratory tract was discussed,and the airflow movement in human upper respiratory tract was analyzed.Results showed that in the low intensive respiratory patterns,human upper respiratory tract moves backward,the maximum displacement of the tertiary bronchus was 4.99 mm,the anterior wall was stretched,and the posterior wall was compressed.The wall shearing stress in the mouth-throat model was larger than that in the trachea-triple bifurcation,and the maximum shearing stress was 30.34 Pa.The maximum of airflow velocity reached maximum at 7.85 m/s in the glottis.The phenomenon of airflow separation appeared near the outer wall of the pharynx and the trachea,and the high velocity zone was created near the inner wall of the trachea.The airflow split at the divider and high velocity zone was generated near the inner wall of the trachea.