Theoretical and Experimental Investigation of Acoustic Agglomeration of Aerosol Particulates

Abstract

This report aims to investigate the theoretical and experimental aspects of Acoustic Agglomeration. Phenomenon, where small particles under periodic motion in the fluid approach each other forming large agglomerates. This process is governed by different hydrodynamic mechanisms, and the efficiency of agglomeration depends on the frequency of the acoustic pressure. Our investigation is restricted to SiO2 particles with diameter from 0.3 to 10 µm subjected to a frequency of 500 to 3000 Hz. Various interaction mechanisms comprising binary interaction of particles, contribution of third particles, and collected behaviour of multiparticle systems are investigated numerically in the framework of DEM. A comprehensive study of very fine particles in DEM was performed that included orthokinetic agglomeration and acoustic wake effects. The same selected samples were tested by applying the CFD approach. The analogous agglomeration mechanism was also investigated experimentally. The experimental facility adopted to investigate particle emission in real conditions was located in an industrial chimney system.