[Table of Contents]

Plasma and Fusion Research

Volume 5, S1051 (2010)

Regular Articles

Binary Interaction Approximation to N-Body Problems
Shun-ichi OIKAWA and Hideo FUNASAKA
Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan
(Received 6 January 2009 / Accepted 16 May 2009 / Published 26 March 2010)

Abstract

The binary interaction approximation (BIA) to N-body problems is proposed. The BIA conserves total linear momenta in principle. Other invariants, such as the total angular momentum and total energy, are conserved to at least 12 effective digits for a two-dimensional hydrogen plasma of T = 10 keV and n = 1020 m−3. For such a plasma, the total CPU time of the BIA is found to scale as approximately N1.9, while the conventional direct integration method scales as approximately N3.

Keywords

N-body problem, algebraic approximation, binary interaction approximation, variable step size, parallel computation.

DOI: 10.1585/pfr.5.S1051

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This paper may be cited as follows:

Shun-ichi OIKAWA and Hideo FUNASAKA, Plasma Fusion Res. 5, S1051 (2010).