Flocs restructuring during aggregation: Experimental evidence and numerical simulation

Aggregate structure, i.e., fractal dimension, has a coupled geometric and h ydrodynamic impact on the aggregate collision frequencies. In this work, we evaluated different collision frequency kernel calculation schemes to simu late experimentally determined latex particle aggregation kinetics. Light s cattering was used to simultaneously measure aggregate size and fractal dim ension throughout the latex aggregation experiments. The intermediate colli sion scheme proposed by Veerepanneni and Wiesner (J. Colloid Interface Sci. 177, 45-57 (1996)) is in agreement with experimental aggregation kinetics if considered along with experimentally determined fractal dimension evolut ion. Aggregate restructuring was found to be an important mechanism in expl aining aggregation kinetics. (C) 2001 Academic Press.