Dust Agglomeration

Institut für Geophysik und extraterrestrische Physik, Technische Universität zu Braunschweig, Mendelssohnstr. 3, 38106 Braunschweig, Germany

Corresponding author: j.blum@tu-bs.de

Abstract

This article is intended to be used as an introduction to the problem of protoplanetary dust aggregation. The basic concept of dust aggregation and its description by Smoluchowski's equation are presented. Analytic solutions to Smoluchowski's equation are explored which show some characteristics of the more general solutions, such as self-similarity and scaling behavior. The physics of dust aggregation is treated through interaction forces between the particles and empirical data on sticking efficiencies and particle morphologies in dust-dust collisions. Aggregate morphologies are described by the fractal concept, and its implications for collision cross sections and collision velocities are discussed. Theoretical and experimental work on collision-induced restructuring and fragmentation of fractal and non-fractal dust aggregates is presented. Finally, the latest modelling approaches for protoplanetary dust growth are discussed.