Since end of 2019 the COVID-19 pandemic, caused by the SARS-CoV-2 virus, is threatening humanity. Despite the fact that various scientists across the globe try to shed a light on this new respiratory disease, it is not yet fully understood. Unlike many studies on the geographical spread of the pandemic, including the study of external transmission routes, this work focuses on droplet and aerosol transport and their deposition inside the human airways. For this purpose, a digital replica of the human airways is used and particle transport under various levels of cardiovascular activity in enclosed spaces is studied by means of computational fluid dynamics. The influence of the room size, where the activity takes place, and the aerosol concentration is studied. The contribution aims to assess the risk of various levels of exercising while inhaling infectious pathogens to gain further insights in the deposition behavior of aerosols in the human airways. The size distribution of the expiratory droplets or aerosols plays a crucial role for the disease onset and progression. As the size of the expiratory droplets and aerosols differs for various exhaling scenarios, reported experimental particle size distributions are taken into account when setting up the environmental conditions. To model the aerosol deposition we employ \(\text{OpenFOAM}\) by using an Euler-Lagrangian frame including Reynolds-Averaged Navier–Stokes resolved turbulent flow. Within this study, the effects of different exercise levels and thus breathing rates as well as particle size distributions and room sizes are investigated to enable new insights into the local particle deposition in the human airway and virus loads. A general observation can be made that exercising at higher levels of activity is increasing the risk to develop a severe cause of the COVID-19 disease due to the increased aerosolized volume that reaches into the lower airways, thus the knowledge of the inhaled particle dynamics in the human airways at various exercising levels provides valuable information for infection control strategies.

自 2019 年底以来，由 SARS-CoV-2 病毒引起的 COVID-19 大流行正在威胁人类。尽管全球各地的科学家都试图阐明这种新的呼吸道疾病，但尚未完全了解。与许多关于大流行的地理传播的研究（包括对外部传播途径的研究）不同，这项工作的重点是飞沫和气溶胶的运输及其在人体气道内的沉积。为此，使用了人体气道的数字复制品，并通过计算流体动力学研究了封闭空间中不同心血管活动水平下的粒子传输。研究了房间大小、活动发生地和气溶胶浓度的影响。该贡献旨在评估在吸入传染性病原体时进行不同程度运动的风险，以进一步了解气溶胶在人体气道中的沉积行为。呼出液滴或气溶胶的大小分布对疾病的发作和进展起着至关重要的作用。由于呼气液滴和气溶胶的大小因各种呼气场景而异，因此在设置环境条件时会考虑报告的实验粒径分布。为了模拟气溶胶沉积，我们采用 由于呼气液滴和气溶胶的大小因各种呼气场景而异，因此在设置环境条件时会考虑报告的实验粒径分布。为了模拟气溶胶沉积，我们采用 由于呼气液滴和气溶胶的大小因各种呼气场景而异，因此在设置环境条件时会考虑报告的实验粒径分布。为了模拟气溶胶沉积，我们采用\(\text{OpenFOAM}\) 通过使用包括 Reynolds-Averaged Navier–Stokes 在内的 Euler-Lagrangian 框架解决了湍流。在这项研究中，研究了不同运动水平以及呼吸频率以及颗粒大小分布和房间大小的影响，以便对人体气道中的局部颗粒沉积和病毒载量提供新的见解。一般的观察结果是，由于进入下气道的雾化体积增加，因此在较高的活动水平下锻炼会增加导致 COVID-19 疾病的严重病因的风险，因此了解吸入颗粒动力学不同运动水平的人体气道为感染控制策略提供了有价值的信息。