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arXiv · 2112.13193

Aggregation in non-uniform systems with advection and localized source

Rishat R. Zagidullin·Alexander P. Smirnov·Sergey A. Matveev·Nikolai V. Brilliantov·P. L. Krapivsky
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Abstract

We explore analytically and numerically agglomeration driven by advection and localized source. The system is inhomogeneous in one dimension, viz. along the direction of advection. We analyze a simplified model with mass-independent advection velocity, diffusion coefficient, and reaction rates. We also examine a model with mass-dependent coefficients describing aggregation with sedimentation. For the simplified model, we obtain an exact solution for the stationary spatially dependent agglomerate densities. In the model describing aggregation with sedimentation, we report a new conservation law and develop a scaling theory for the densities. For numerical efficiency we exploit the low-rank approximation technique; this dramatically increases the computational speed and allows simulations of large systems. The numerical results are in excellent agreement with the predictions of our theory.

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Rishat R. Zagidullin, Alexander P. Smirnov, Sergey A. Matveev, Nikolai V. Brilliantov, P. L. Krapivsky. 2021-12-25. Aggregation in non-uniform systems with advection and localized source. https://doi.org/10.1088/1751-8121%2Fac711a

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