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arXiv · 1204.6512

An adaptive, high-order phase-space remapping for the two-dimensional Vlasov-Poisson equations

Bei Wang·Greg Miller·Phil Colella
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Abstract

The numerical solution of high dimensional Vlasov equation is usually performed by particle-in-cell (PIC) methods. However, due to the well-known numerical noise, it is challenging to use PIC methods to get a precise description of the distribution function in phase space. To control the numerical error, we introduce an adaptive phase-space remapping which regularizes the particle distribution by periodically reconstructing the distribution function on a hierarchy of phase-space grids with high-order interpolations. The positivity of the distribution function can be preserved by using a local redistribution technique. The method has been successfully applied to a set of classical plasma problems in one dimension. In this paper, we present the algorithm for the two dimensional Vlasov-Poisson equations. An efficient Poisson solver with infinite domain boundary conditions is used. The parallel scalability of the algorithm on massively parallel computers will be discussed.

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Bei Wang, Greg Miller, Phil Colella. 2012-04-29. An adaptive, high-order phase-space remapping for the two-dimensional Vlasov-Poisson equations. https://doi.org/10.1137/120872954

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