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arXiv · 1412.4720

Advection diffusion equation with absorbing boundary

John Grant·Michael Wilkinson
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Abstract

We consider a spatially homogeneous advection-diffusion equation in which the diffusion tensor and drift velocity are time-independent, but otherwise general. We derive asymptotic expressions, valid at large distances from a steady point source, for the flux onto a completely permeable boundary and onto an absorbing boundary. The absorbing case is treated by making a source of antiparticles at the boundary. In both cases there is an exponential decay as the distance from the source increases; we find that the exponent is the same for both boundary conditions.

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John Grant, Michael Wilkinson. 2014-12-15. Advection diffusion equation with absorbing boundary. https://doi.org/10.1007/s10955-015-1257-2

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