| We present a coupled model for advection, aggregation and fragmentation that is based on the dynamics of individual, spherical inertial particles in two-dimensional periodic flows. Due to the particle inertia advection leads to the accumulation of the particles on attractors in the flow. The collision of the particles leads to aggregation and larger aggregates are formed. These can in turn fragment due to shear forces in the flow. We find that the combination of aggregation and fragmentation leads to an asymptotic steady state for the size distribution of the aggegates which depends crucially on the considered mechanism of fragmentation. Furthermore, we take into account that real particles are not spheres but possess instead irregular shapes which can approximately described by a fractal dimension. We demonstrate how this fractal dimension and well as the binding strength of the aggregates influences the shape of the resulting size distribution. Finally, we apply this approach to experiments studying aggregation and fragmentation dynamics of marine aggregates in a rotating cylinder. |
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