SCL member Igor Stankovic held a talk at the colloquium of III45018 project entitled "Agglomeration kinetics and numerical methods for characterization of nano-particle agglomerates".

Abstract:

We revisit the aggregation dynamics of particles interacting with short-range attractive interaction. Using Brownian Dynamics simulations we follow the relaxation of a homogeneous, thermodynamically unstable system towards equilibrium by agglomeration. The dynamics of this transition is found to be subdiffusive and characterized by the creation of clusters exhibiting an exponential size distribution. If particle density is sufficiently high, formed clusters will further agglomerate into a single cluster spanning the system. We introduce a phenomenological time scaling law in order to collapse data for a range of diffusion rates and densities onto a single universal curve. Furthermore we demonstrate, that this class of systems and their dynamical features can be modelled by a fractional Smoluchowski coagulation equation. The underlying coagulation rates are seen to exhibit a simple dependency on cluster size. Agglomeration of particles in suspensions is common in many technological and biological processes and their unusual properties are intensively exploited in industrial applications, from environment protection to nano-particle production. Approximate description of structural parameters evolution introduced here should be applicable to the family of systems where agglomeration and diffusion rates are comparable.