Fig. 2: The pore networks modelling (PNM) of the three commercial face masks and their pore diameter distribution.
From: Microstructure analysis and image-based modelling of face masks for COVID-19 virus protection
The air phase (as shown in Fig. 1) is represented as a series of spheres connected by narrower throats (shown as lines). The assigned-colour spheres represent pores scaled according to their equivalent radius (in the range of 0–50 µm). The fibres superimposed with pore networks are shown in a, d, g the pores and throats b, e, h indicate the porosity within the sample volume. The associated pore diameter distributions c, f, i are quantified to evaluate the droplets filtration efficiency when cough or sneezing.
