The present study aims to investigate the effect of swirling flow on particle deposition in a realistic human airway. A computational fluid dynamic (CFD) model was utilized for the simulation of oral inhalation and particle transport patterns, considering the k-ω turbulence model. Lagrangian particle tracking was used to track the particles’ trajectories. A normal breathing condition (30 L/min) was applied, and two-micron particles were injected into the mouth, considering swirling flow to the oral inhalation airflow. Different cases were considered for releasing the particles, which evaluated the impacts of various parameters on the deposition efficiency (DE), including the swirl intensity, injection location and pattern of the particle. The work's novelty is applying several injection locations and diameters simultaneously. The results show that the swirling flow enhances the particle deposition efficiency (20–40%) versus no-swirl flow, especially in the mouth. However, releasing particles inside the mouth, or injecting them randomly with a smaller injection diameter (d_inj) reduced DE in swirling flow condition, about 50 to 80%. Injecting particles inside the mouth can decrease DE by about 20%, and releasing particles with smaller d_inj leads to 50% less DE in swirling flow. In conclusion, it is indicated that the airflow condition is an important parameter for a reliable drug delivery, and it is more beneficial to keep the inflow uniform and avoid swirling flow.

本研究旨在研究旋流对现实人体气道中颗粒沉积的影响。考虑到k - ω，计算流体动力学 (CFD) 模型用于模拟口腔吸入和粒子传输模式湍流模型。拉格朗日粒子跟踪用于跟踪粒子的轨迹。应用正常呼吸条件（30 L/min），将两微米颗粒注入口腔，考虑到口腔吸入气流的涡流。考虑了释放颗粒的不同情况，评估了各种参数对沉积效率（DE）的影响，包括颗粒的涡流强度、注入位置和图案。这项工作的新颖之处在于同时应用了多个注射位置和直径。结果表明，与无旋流相比，旋流提高了颗粒沉积效率（20-40%），尤其是在口腔中。但是，在口腔内释放颗粒，或以较小的注射直径随机注射（d_inj ) 降低涡流条件下的 DE，约 50% 至 80%。将颗粒注入口内可降低约 20% 的 DE，而释放d _inj较小的颗粒可使涡流中的 DE 降低 50%。总之，表明气流条件是可靠药物输送的重要参数，更利于保持流入均匀，避免涡流。