Research output: Contribution to journal › Article › peer-review
Mesh-free stochastic algorithms for systems of drift–diffusion–reaction equations and anisotropic diffusion flux calculations. / Sabelfeld, Karl.
In: Probabilistic Engineering Mechanics, Vol. 61, 103065, 07.2020.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Mesh-free stochastic algorithms for systems of drift–diffusion–reaction equations and anisotropic diffusion flux calculations
AU - Sabelfeld, Karl
PY - 2020/7
Y1 - 2020/7
N2 - We suggest in this paper two new random walk based stochastic algorithms for solving high-dimensional PDEs for domains with complicated geometrical structure. The first one, a Random Walk on Spheres (RWS) algorithm is developed for solving systems of coupled drift–diffusion–reaction equations where the random walk is living both on randomly sampled spheres and inside the relevant balls. The second method suggested solves transient anisotropic diffusion equations, where the random walk is carried out on random rectangular parallelepipeds inside the domain. The two methods are mesh-free both in space and time, and are well applied to solve high-dimensional problems with complicated domains. The algorithms are based on tracking the trajectories of the diffusing particles exactly in accordance with the probabilistic distributions derived from the explicit representation of the relevant Green functions for a sphere and a parallelepiped. They can be conveniently used not only for the solutions, but also for a direct calculation of fluxes to any part of the boundary without calculating the whole solution in the domain. Applications to exciton transport in semiconductors and related cathodoluminescence imaging of a set of randomly distributed threading dislocations are presented.
AB - We suggest in this paper two new random walk based stochastic algorithms for solving high-dimensional PDEs for domains with complicated geometrical structure. The first one, a Random Walk on Spheres (RWS) algorithm is developed for solving systems of coupled drift–diffusion–reaction equations where the random walk is living both on randomly sampled spheres and inside the relevant balls. The second method suggested solves transient anisotropic diffusion equations, where the random walk is carried out on random rectangular parallelepipeds inside the domain. The two methods are mesh-free both in space and time, and are well applied to solve high-dimensional problems with complicated domains. The algorithms are based on tracking the trajectories of the diffusing particles exactly in accordance with the probabilistic distributions derived from the explicit representation of the relevant Green functions for a sphere and a parallelepiped. They can be conveniently used not only for the solutions, but also for a direct calculation of fluxes to any part of the boundary without calculating the whole solution in the domain. Applications to exciton transport in semiconductors and related cathodoluminescence imaging of a set of randomly distributed threading dislocations are presented.
KW - A system of drift–diffusion–reaction equations
KW - Anisotropic diffusion
KW - First passage algorithms
KW - Random walk on cubes
KW - Random walk on spheres and balls
KW - A system of drift-diffusion-reaction equations
KW - FLOATING RANDOM-WALK
UR - http://www.scopus.com/inward/record.url?scp=85082687282&partnerID=8YFLogxK
U2 - 10.1016/j.probengmech.2020.103065
DO - 10.1016/j.probengmech.2020.103065
M3 - Article
AN - SCOPUS:85082687282
VL - 61
JO - Probabilistic Engineering Mechanics
JF - Probabilistic Engineering Mechanics
SN - 0266-8920
M1 - 103065
ER -
ID: 23948918