MHD simulation on magnetic compression of field reversed configurations with NIMROD

Nuclear Fushion

article

Y. Ma¹  P. Zhu¹  B. Rao¹  H. Li³ 

[1] International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics, State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology;Department of Engineering Physics, University of Wisconsin-Madison;College of Physics and Optoelectronic Engineering, Shenzhen University

关键词: field reversed configuration;    compact toroid;    magnetic compression;    MHD simulation;   

DOI  :  10.1088/1741-4326/acbdac

来源: Institute of Physics Publishing Ltd.

【 摘 要 】

Magnetic compression has long been proposed a promising method for plasma heating in a field reversed configuration (FRC). However, it remains a challenge to fully understand the physical mechanisms underlying the compression process, due to its highly dynamic nature beyond the one-dimensional (1D) adiabatic theory model (Spenceret al1983Phys. Fluids261564). In this work, magnetohydrodynamics simulations on the magnetic compression of FRCs using the NIMROD code (Sovinecet al2004J. Comput. Phys.195355) and their comparisons with the 1D theory have been performed. The effects of the assumptions of the theory on the compression process have been explored, and the detailed profiles of the FRC during compression have been investigated. The pressure evolution agrees with the theoretical prediction under various initial conditions. The axial contraction of the FRC can be affected by the initial density profile and the ramping rate of the compression magnetic field, but the theoretical predictions on the FRC's length in general and the relation r_s = sqrt{2}r_oin particular hold approximately well during the whole compression process, wherer _s is the major radius of FRC separatrix andr _o is that of the magnetic axis. The evolutions of the density and temperature can be affected significantly by the initial equilibrium profile and the ramping rate of the compression magnetic field. During the compression, the major radius of the FRC is another parameter that is susceptible to the ramping rate of the compression field. Basically, for the same magnetic compression ratio, the peak density is higher and the FRC's radiusr _s is smaller than the theoretical predictions.

【 授权许可】

Unknown