Simplex-in-cell technique for collisionless plasma simulations

JOURNAL OF COMPUTATIONAL PHYSICS

卷:304

Article

Kates-Harbeck, Julian¹  Totorica, Samuel¹  Zrake, Jonathan¹  Abel, Tom^1,2 

[1] Stanford Univ, Kavli Inst Particle Astrophys & Cosmol, SLAC Natl Accelerator Lab, Menlo Pk, CA 94025 USA

[2] Inst Astrophys, Inst Lagrange Paris, F-75014 Paris, France

关键词: Vlasov equation;    N-body;    Numerical;    Particle-in-cell;   

DOI  :  10.1016/j.jcp.2015.10.017

来源: Elsevier

【 摘 要 】

We extend the simplex-in-cell (SIC) technique recently introduced in the context of collisionless dark matter fluids[ 1,2] to the case of collisionless plasmas. The six-dimensional phase space distribution function f(x, v) is represented by an ensemble of three-dimensional manifolds, which we refer to as sheets. The electric potential field is obtained by solving the Poisson equation on a uniform mesh, where the charge density is evaluated by a spatial projection of the phase space sheets. The SIC representation of phase space density facilitates robust, high accuracy numerical evolution of the Vlasov-Poisson system using significantly fewer tracer particles than comparable particle-in-cell (PIC) approaches by reducing the numerical shot-noise associated with the latter. We introduce the SIC formulation and describe its implementation in a new code, which we validate using standard test problems including plasma oscillations, Landau damping, and two stream instabilities in one dimension. Merits of the new scheme are shown to include higher accuracy and faster convergence rates in the number of particles. We finally motivate and outline the efficient application of SIC to higher dimensional problems. (C) 2015 Elsevier Inc. All rights reserved.

【 授权许可】

Free