Measurement of the porosity of a pseudo-spherical nanostructured particle deposit formed by filtration

Abstract

In many applications involving nanoparticles, the question of controlling the properties of the films formed (particularly in terms of porosity) remains incomplete. These applications cover an extensive array of fields ranging from the manufacture of nanofilms to the prediction of the pressure drop of nanoparticle films formed on the surface of air purification filters. A review of the literature shows that the porosity of nanometric particle deposits has mainly been studied by numerical simulation. The few experimental studies conducted have focused on micron-sized particles or nanoparticle aggregates under limited operating conditions. The objective of this study is to confirm the porosity results of nanometric particle deposits obtained by the previous simulations and to correlate the porosity with relevant dimensionless numbers. The changes in porosity according to the various operating conditions confirm those obtained during the numerical simulations. All the experimental porosity values could be correlated to the Stokes number alone.