Abstract Details
Abstracts
Author: William J. White
Requested Type: Poster
Submitted: 2026-03-18 15:27:46
Co-authors: S. E. Clark
Contact Info:
Helion Energy, Inc.
1415 75th St SW
Everett, WA 98203
USA
Abstract Text:
The global stability of field-reversed configuration (FRC) plasmas has proven challenging to predict theoretically and to characterize experimentally, and is crucial for magneto-inertial fusion applications. Destructive modes like the $n=1$, $m=1$ tilt mode and the $n=2$ rotational mode can quickly disrupt equilibrium and lead to the loss of magnetic confinement, but predicting their onset is not simple. Further, nonlinear effects like modal saturation and tearing can greatly alter the observed coherent lifetime of the plasma. In this work, we probe the global stability of FRC plasmas in a wide range of regimes and investigate the mechanisms for stability and instability via hybrid fluid-kinetic simulations conducted with the WarpX code. Through varying the kinetic $S^*$ and $s$ parameters, as well as the geometric elongation $E$, we characterize the stability and lifetimes of the simulated FRC plasmas and propose plasma regimes that are expected to produce long lifetimes. Additionally, by fixing the kinetic parameters and simultaneously changing the external field and the temperature we demonstrate that high-flux FRC plasmas initially in equilibrium are prone to catastrophic tilting on a time scale proportional to the flux, matching MHD predictions. The stability of an FRC undergoing a quasi-static adiabatic compression is simulated by generating equilibria along an adiabatic curve and evaluating the stability properties, which showed predictions consistent with MHD. Finally, we discuss algorithmic changes that have been implemented to improve conservation properties and reduce numerical noise, which are crucial for accurately simulating the long-term evolution of FRC plasmas.
Characterization: 1.0
Comments: