稳态条件下气溶胶粒子在口腔模型中的沉淀率

Deposition Efficiencies of Aerosol Particles in Human Oral Airway Model under Stable Condition

以实际人体解剖学数据为基础,利用流体力学软件构建了口腔模型。由于口腔形状不规则,流场中会有湍流产生,所以本文选用的是k-ω方程。在此基础上,假设吸入空气流量为一个常量,改变吸入气体、气溶胶粒子的物理参数,以调整St数的变化,模拟不同情况下气溶胶粒子运动情况。由模拟结果可知:气溶胶粒子在口腔中的沉淀率受粒子半径、密度、及流速的影响,并随这些量的增加而增加;沉淀率可以视作St数的函数,并随St数的增加而增加;气溶胶粒子在口腔中的沉淀分布受模型几何形状和湍流的影响,在喉部附近沉淀较为明显;粒子在口腔中将沿怎样的轨迹运动则取决于粒子在入口处的初始位置。

According to the anatomy date, the oral airway model was established with hydrodynamics software. κ-ω function was selected to adapt the abnormatly geometrical shape turbulent fluid field. The particle movements were simulated under different Stokes number varying with the flow rate, aerosols diameter and density, where the flow rate was set as a constant to investigate the deposition efficiencies under steady condition. The result shows that the deposition efficiency in oral airway are affected by the particle diameter, density and flow rate, and increases with them the deposition efficiency can be regarded as the function of Stocks number, and increases with it; the particles deposit mainly near the laryngeal due to the effect of turbulent flow and geometric feature, and the trajectories also depend on the inlet position.