Robinson Joshua F, Rios de Anda Ioatzin, Moore Fergus J, Reid Jonathan P, Sear Richard P, Royall C Patrick
H. H. Wills Physics Laboratory, University of Bristol, Bristol BS8 1TL, United Kingdom.
School of Chemistry, Cantock's Close, University of Bristol, Bristol BS8 1TS, United Kingdom.
Phys Fluids (1994). 2021 Apr;33(4):043112. doi: 10.1063/5.0047622. Epub 2021 Apr 27.
In the COVID-19 pandemic, among the more controversial issues is the use of masks and face coverings. Much of the concern boils down to the question-just how effective are face coverings? One means to address this question is to review our understanding of the physical mechanisms by which masks and coverings operate-steric interception, inertial impaction, diffusion, and electrostatic capture. We enquire as to what extent these can be used to predict the efficacy of coverings. We combine the predictions of the models of these mechanisms which exist in the filtration literature and compare the predictions with recent experiments and lattice Boltzmann simulations, and find reasonable agreement with the former and good agreement with the latter. Building on these results, we explore the parameter space for woven cotton fabrics to show that three-layered cloth masks can be constructed with comparable filtration performance to surgical masks under ideal conditions. Reusable cloth masks thus present an environmentally friendly alternative to surgical masks so long as the face seal is adequate enough to minimize leakage.
在新冠疫情期间，口罩和面罩的使用是争议较大的问题之一。大部分担忧归根结底是这个问题——面罩究竟有多大效果？解决这个问题的一个方法是回顾我们对口罩和面罩发挥作用的物理机制的理解——空间拦截、惯性碰撞、扩散和静电捕获。我们探究这些机制在多大程度上可用于预测面罩的功效。我们结合了过滤文献中存在的这些机制的模型预测，并将这些预测与近期实验和格子玻尔兹曼模拟进行比较，发现与前者有合理的一致性，与后者有良好的一致性。基于这些结果，我们探索了机织棉织物的参数空间，以表明在理想条件下，可以制作出过滤性能与外科口罩相当的三层布口罩。因此，只要面部密封足够好以尽量减少泄漏，可重复使用的布口罩就为外科口罩提供了一种环保替代品。
