Agglomeration Dynamics of Non-Spherical Nanoparticles in Homogeneous Isotropic Turbulence

Abstract The present study investigates the agglomeration of nanoparticles under the joint influence of Brownian motion and turbulent shear using direct numerical simulations. Under these conditions, it is still unclear how different turbulence parameters affect the agglomeration dynamics and particle morphology. Our computations resolve the trajectories of individual agglomerates, enabling a direct, model-free description of their fractal morphology. Specifically, we find that both the morphology and agglomeration rate are largely insensitive to the Reynolds number. In contrast, smaller Kolmogorov scales lead to an accelerated agglomeration process. The smallest turbulent eddies also influence agglomerate morphology, with more compact structures forming at smaller Kolmogorov scales. Additionally, we demonstrate that the agglomeration dynamics observed in detailed simulations can be reproduced using a population balance model that incorporates a recently proposed expression for the agglomerate collision frequency.