Invariant regimes of Spencer scaling law for magnetic compression of rotating FRC plasma

作     者：Ma, Yiming Zhu, Ping Rao, Bo Li, Haolong 

作者机构：State Key Laboratory of Advanced Electromagnetic Technology International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics School of Electrical and Electronic Engineering Huazhong University of Science and Technology Wuhan430074 China Department of Nuclear Engineering and Engineering Physics University of Wisconsin-Madison MadisonWI53706 United States College of Physics and Optoelectronic Engineering Shenzhen University Shenzhen518060 China 

出 版 物：《arXiv》 (arXiv)

年 卷 期：2024年

核心收录：

主　　题：Scaling laws 

摘      要：The scaling laws for the magnetic compression of a toroidally rotating field reversed configuration (FRC) have been investigated in this work. The magnetohydrodynamics (MHD) simulations of the magnetic compression on rotating FRCs employing the NIMROD code [C. R. Sovinec et al., J. Comput. Phys. 195, 355 (2004)], are compared with the Spencer’s one-dimensional (1D) theory [R. L. Spencer et al., Phys. Fluids 26, 1564 (1983)] for a wide range of initial flow speeds and profiles. The toroidal flow can influence the scalings directly through the alteration of the compressional work as also evidenced in the 1D adiabatic model, and indirectly by reshaping the initial equilibrium. However, in comparison to the static initial FRC equilibrium cases, the pressure and the radius scalings remain invariant for the magnetic compression ratio Bw2/Bw1 up to 6 in presence of the initial equilibrium flow, suggesting a broader applicable regime of the Spencer scaling law for FRC magnetic compression. The invariant scaling has been proven a natural consequence of the conservation of angular momentum of both fluid and magnetic field during the dynamic compression process. Copyright © 2024, The Authors. All rights reserved.