微颗粒在人体上呼吸道中运动沉积的数值模拟

Numerical simulation of micro-particle movement and deposition in human upper respiratory tract

为了揭示在人体上呼吸道中气流和微细颗粒的运动沉积规律,采用数值分析方法进行了研究.在广泛参考各种上呼吸道模型的基础上,建立了一个新的完整的从口腔-咽-喉-气管-支气管的三维几何模型.采用RNGk-ε模型描述气体的流动,并在拉格朗日框架下追踪颗粒运动.计算得到了模型内详细的流场和颗粒在不同部位的沉积情况,结果表明,颗粒沉积率主要取决于气流流速与颗粒惯性大小.为了验证模型的合理性与结果的正确性,将不同工况下颗粒沉积率的数值计算值与实验数据进行了比较,结果发现两者较吻合.

In this work numerical analysis method was applied to study the airflow and micro-particle movement and deposition. Based on various geometrical models of the human upper respiratory tract, a new entire three-dimensional geometry from mouth, pharynx, larynx, trachea to bronchi was proposed in this study. RNG k-ε turbulence model was used to describe the gas flow and the particles were traced in the Lagrangian frame. The detailed gas flow field and deposition of particles in different parts were computed. The results showed that the particle deposition depended on velocity of flow and inertia of particles. To validate the reasonability of the model and the correctness of the results, deposition of particles under different cases was studied numerically, indicating that the particle deposition predicted by numerical simulation agreed well with experimental data.