Arpino Fausto, Grossi Giorgio, Cortellessa Gino, Mikszewski Alex, Morawska Lidia, Buonanno Giorgio, Stabile Luca
Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, FR, Italy.
International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, Queensland, Australia.
Indoor Air. 2022 Mar;32(3):e13012. doi: 10.1111/ina.13012.
In this study, the risk of infection from SARS-CoV-2 Delta variant of passengers sharing a car cabin with an infected subject for a 30-min journey is estimated through an integrated approach combining a recently developed predictive emission-to-risk approach and a validated CFD numerical model numerically solved using the open-source OpenFOAM software. Different scenarios were investigated to evaluate the effect of the infected subject position within the car cabin, the airflow rate of the HVAC system, the HVAC ventilation mode, and the expiratory activity (breathing vs. speaking). The numerical simulations here performed reveal that the risk of infection is strongly influenced by several key parameters: As an example, under the same ventilation mode and emitting scenario, the risk of infection ranges from zero to roughly 50% as a function of the HVAC flow rate. The results obtained also demonstrate that (i) simplified zero-dimensional approaches limit proper evaluation of the risk in such confined spaces, conversely, (ii) CFD approaches are needed to investigate the complex fluid dynamics in similar indoor environments, and, thus, (iii) the risk of infection in indoor environments characterized by fixed seats can be in principle controlled by properly designing the flow patterns of the environment.
在本研究中，通过一种综合方法估计了与感染对象在汽车车厢内共享30分钟行程的乘客感染新冠病毒德尔塔变种的风险，该方法结合了最近开发的预测排放到风险的方法和使用开源OpenFOAM软件数值求解的经过验证的计算流体动力学（CFD）数值模型。研究了不同场景，以评估感染对象在车厢内的位置、暖通空调（HVAC）系统的气流速率、HVAC通风模式以及呼气活动（呼吸与说话）的影响。这里进行的数值模拟表明，感染风险受到几个关键参数的强烈影响：例如，在相同的通风模式和排放场景下，感染风险随着HVAC流速的变化从零到大约50%不等。获得的结果还表明，（i）简化的零维方法限制了对此类密闭空间中风险的正确评估，相反，（ii）需要CFD方法来研究类似室内环境中的复杂流体动力学，因此，（iii）在以固定座椅为特征的室内环境中，感染风险原则上可以通过合理设计环境的流动模式来控制。
