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arXiv · 2306.10794

General Local Reactive Boundary Condition for Dissolution and Precipitation Using the Lattice Boltzmann Method

Julius Weinmiller·Martin P. Lautenschlaeger·Benjamin Kellers·Timo Danner·Arnulf Latz
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Abstract

A general and local reactive boundary condition (RBC) for studying first-order equilibrium reactions using the lattice Boltzmann method (LBM) is presented. Its main characteristics are accurate reproduction of wall diffusion, invariance to the wall and grid orientation, and absence of nonphysical artefacts. The scheme is successfully tested for different benchmark cases considering diffusion, advection, and reactions of fluids at solid-liquid interfaces. Unlike other comparable RBCs from the literature, the novel scheme is valid for a large range of Péclet and Damköhler numbers, and shows realistic pattern formation during precipitation. In addition, quantitative results are in good accordance with analytical solutions and values from literature. Combining the new RBC with the rest fraction method, Péclet-Reynolds ratios of up to 1000 can be achieved. Overall, the novel RBC accurately models first-order reactions, is applicable for complex geometries, and allows efficiently simulating dissolution and precipitation phenomena in fluids at the pore scale.

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Julius Weinmiller, Martin P. Lautenschlaeger, Benjamin Kellers, Timo Danner, Arnulf Latz. 2023-06-19. General Local Reactive Boundary Condition for Dissolution and Precipitation Using the Lattice Boltzmann Method. https://arxiv.org/abs/2306.10794

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