Study on the Interaction between Modes of a Nanoparticle-Laden Aerosol System

Abstract

Nanoparticle-laden two-phase flow systems, especially atmospheric aerosols, are usually found with several modes for particle size distribution (PSD). For the first time, a mathematical method is proposed to study the interaction of nanoparticle dynamics between modes by establishing two joint population balance equations (PBEs). The PBEs are solved using the sectional method, which divides the PSD into discrete bins. The nanoparticle-laden system involves Brownian coagulation, ventilation, and injection. The interaction between modes within a size distribution is studied quantitatively with and without injection and ventilation. The study shows that particles with smaller size are easier to be removed by background particles, but the lag time to be removed is affected by not only the total number concentration of small particles but also their sizes. Background particles play an important role in determining the evolution of small particle system, whose presence makes the secondary model absent for the small particles.