Simulations of Thin-Foil Liner Implosions Driven by a Dynamic Screw Pinch

Magnetically driven liner implosion experiments are conducted to generate and study fusion plasmas for energy, basic science, and stockpile stewardship applications. One of the challenges associated with the liner implosion method is that instabilities, such as the magneto-Rayleigh-Taylor instability (MRTI), develop during the implosions. These instabilities degrade the implosion symmetry and reduce fusion performance. Dynamic screw pinch (DSP) configurations on thin foil liner implosions have shown reduced MRTI amplitudes compared to standard z-pinch (SZP) configurations [ P. C. Campbell et al. , PRL 125 , 035001 (2020) ]. MRTI from SZP and DSP cases are analyzed using PERSEUS [ C. E. Seyler and M. R. Martin, Phys. Plasmas 18 , 012703 (2011) ], an extended magnetohydrodynamics (MHD) code. MRTI modes, average instability amplitudes, and liner implosion trajectories are analyzed from simulation. These simulations are compared to SZP and DSP experiments conducted on the 1-MA COBRA pulsed-power driver to better understand the relative stabilization obtained with the DSP configuration.