Gas-Puff Z-Pinch Simulations Using Cell-Centered Divergence Cleaning

Z-pinches are a widely studied method for plasma confinement in fusion research. To better

understand and optimize plasma behavior, both experiments and numerical simulations are

employed - particularly for gas-puff Z-pinches, which offer a flexible platform for studying plasma

dynamics and instability development. In this work, we present simulation results of COBRA Z-

pinch experiments, focusing on the behavior of triple gas-puff injectors under purely toroidal

magnetic fields. These simulations explore the evolution of the implosion and the growth of

magnetohydrodynamic instabilities. We use the FLASH code [Fryxell et al. Astrophys. J. Suppl.

Ser. 131, 273, 2000; Tzeferacos et al. High Energy Density Phys. 17, 24, 2015] to model the system

dynamics, incorporating a newly implemented cell-centered divergence cleaning method based on

the Generalized Lagrange Multiplier (GLM) approach [Mignone & Tzeferacos, J. Comput. Phys.

229, 2117, 2010], which ensures solenoidality in the magnetic field evolution.