Simplified models of diffusion in radially-symmetric geometries

نویسندگان

چکیده

We consider diffusion-controlled release of particles from d-dimensional radially-symmetric geometries. A quantity commonly used to characterise such diffusive processes is the proportion remaining within geometry over time, denoted as P(t). The stochastic approach for computing P(t) time-consuming and lacks analytical insight into key parameters while continuum yields complicated expressions that obscure influence complicate process fitting experimental data. In this work, address these issues, we develop several simple surrogate models approximate by matching moments with analogue diffusion model. Surrogate are developed homogeneous slab, circular, annular, spherical shell geometries a constant particle movement probability heterogeneous annular geometries, comprised two concentric layers different probabilities. Each model easy evaluate, agrees well both calculations provides transport system: dimension, diffusivity, boundary conditions.

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ژورنال

عنوان ژورنال: Physica D: Nonlinear Phenomena

سال: 2023

ISSN: ['1872-8022', '0167-2789']

DOI: https://doi.org/10.1016/j.physa.2023.129067