COBRA: An Optimized Code for Fast Analysis of Ideal Ballooning Stability of Three-Dimensional Magnetic Equilibria

Authors: Sanchez R.¹; Hirshman S.P.¹; Whitson J.C.¹; Ware A.S.²

Source: Journal of Computational Physics, Volume 161, Number 2, July 2000 , pp. 576-588(13)

Buy & download fulltext article:

Price: $52.63 plus tax (Refund Policy)

Abstract:

A new, fast, and accurate numerical algorithm to assess stability against ideal ballooning modes in general three-dimensional magnetic configurations of interest to controlled thermonuclear fusion is described. The code for ballooning rapid analysis (COBRA) performs this assessment by solving an eigenvalue problem in the form of a linear second-order ordinary differential equation along magnetic field lines in the configuration. An initial approximation for the eigenvalue is obtained from a fast second order matrix method. In COBRA, this approximate eigenvalue is further refined using a variational principle to obtain fourth-order convergence with the mesh size. Richardson's extrapolation is then applied to a sequence of eigenvalues to estimate the exact eigenvalue using the coarsest possible mesh, thus minimizing the computational time. Copyright 2000 Academic Press.

Language: English

Document Type: Research article

Affiliations: 1: Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831-8070 2: Department of Physics and Astronomy, University of Montana, Missoula, Montana, 59801

Publication date: 2000-07-01