Simons Hour Talk

Near-Axis QI
Dec 21, 2023, 10:00 am11:00 am


Event Description

Abstract:     We develop the formalism of the first order near-axis expansion of the MHD equilibrium equations described in Garren & Boozer (1991), Plunk et al. (2019) and Plunk et al. (2021), for the case of a quasi-isodynamic, N-field period, stellarator symmetric, single-well magnetic field equilibrium. The importance of the magnetic axis shape is investigated, and we conclude that control of the curvature and torsion is crucial to obtain omnigenous configurations with finite aspect ratio and low effective ripple, especially for a higher number of field periods. For this reason a method is derived to construct classes of axis shapes with favourable curvature and torsion. Solutions are presented, including a three-field-period configuration constructed at an aspect ratio of A=20, with a maximum elongation of e=3.2 and an effective ripple under 1%, which demonstrates that high elongation is not a necessary feature of QI stellarators. 

Talk time in other timezones:
AEDT  2:00 AM Fri 22 Dec,
JST  12:00 AM Fri 22 Dec,
CET   4:00 PM Thu 21 Dec,
GMT   3:00 PM Thu 21 Dec,
UTC  15:00    Thu 21 Dec,
EST  10:00 AM Thu 21 Dec,
CST   9:00 AM Thu 21 Dec,
MST   8:00 AM Thu 21 Dec,
PST   7:00 AM Thu 21 Dec
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