Abstract Details
Abstracts
Author: Yao Zhou
Requested Type: Pre-Selected Invited
Submitted: 2017-03-16 17:34:00
Co-authors: Y.-M. Huang, H. Qin, A. Bhattacharjee
Contact Info:
Princeton University
PRINCETON PLASMA PHYSICS LAB
PRINCETON, NJ 08540
United States
Abstract Text:
We revisit Parker's conjecture of current singularity formation in 3D line-tied plasmas, using a recently developed numerical method, variational integration for ideal magnetohydrodynamics in Lagrangian labeling. With the frozen-in equation built-in, the method is free of artificial reconnection, hence arguably an optimal tool for studying current singularity formation. Using this method, we first confirm the formation of current singularity in the Hahm-Kulsrud-Taylor problem in 2D. Then, we extend this problem to 3D line-tied geometry. The linear solution, which is singular in 2D, is found to be smooth for all system lengths. However, with finite amplitude, the linear solution can become pathological when the system is sufficiently long. Accordingly, the nonlinear solutions turn out to be smooth for short systems. Nonetheless, the scaling of peak current density vs. system length suggests that the nonlinear solution may become singular at a finite length. Unfortunately, we can neither confirm nor rule out this possibility conclusively, since we cannot obtain solutions with system length near the extrapolated critical value.
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