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arXiv · 2503.02813

An optimal-transport finite-particle method for driven mass diffusion

Anna Pandolfi·Ignacio Romero·Michael Ortiz
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Abstract

We formulate a finite-particle method of mass transport that accounts for general mixed boundary conditions. The particle method couples a geometrically-exact treatment of advection; Wasserstein gradient-flow dynamics; and a Kullback-Leibler representation of the entropy. General boundary conditions are enforced by introducing an adsorption/depletion layer at the boundary wherein particles are added or removed as dictated by the boundary conditions. We demonstrate the range and scope of the method through a number of examples of application, including absorption of particles into a sphere and flow through pipes of square and circular cross section, with and without occlusions. In all cases, the solution is observed to converge weakly, or in the sense of local averages.

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Anna Pandolfi, Ignacio Romero, Michael Ortiz. 2025-03-04. An optimal-transport finite-particle method for driven mass diffusion. https://arxiv.org/abs/2503.02813

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