Abstract Details
Abstracts
Author: Tyler B Cote
Requested Type: Poster
Submitted: 2019-02-22 12:45:21
Co-authors: T. Weyens, M. Willensdorfer, C.C. Hegna
Contact Info:
University of Wisconsin-Madison
1815 University Ave Apt 314
Madison, Wisconsin 53726
United States
Abstract Text:
Recent work has shown the importance of local 3D magnetic geometry on the stability of localized MHD ballooning instabilities in the presence of applied 3D magnetic perturbations [1]. Experimental results from ASDEX-Upgrade have further identified connections between the helically localized ballooning instabilities and the onset and localization of mitigated ELMs [2]. To better understand the connection between changes in MHD stability due to 3D geometry and ELM mitigation, it is necessary to describe the stability properties of intermediate wavelength global peeling-ballooning modes in 3D pedestals.
In this work, we provide an overview of a new tool being developed for studying these peeling-ballooning modes in 3D: PB3D [3]. A summary of the underlying peeling-ballooning theory is provided. We make connections between the theory underpinning PB3D and the previous work on local 3D magnetic geometry in [1] to identify key dependencies of the 3D geometry that may impact the stability of the peeling-ballooning modes. Additionally, an overview of the numerical techniques utilized in PB3D is given, including a summary of the boundary conditions used to properly handle the vacuum field response to the peeling instability in 3D. Finally, preliminary results are presented for a simple infinite-n ballooning unstable equilibrium to make a direct comparison between the local stability theory used in [1] to global stability solutions provided by PB3D.
[1] T.B. Cote et al 2019 Nuclear Fusion 59 016015
[2] M. Willensdorfer et al 2019 Plasma Physics and Controlled Fusion 61 014019
[3] T. Weyens et al 2017 Journal of Computational Physics 330 997
Comments:
Prefer the "Plasma Properties, Equilibrium, Stability, and Transport" section, could be in "Computer Simulation of Plasmas" if needed.
