Variation of high-power aluminum-wire array Z-pinch dynamics with wire number, load mass, and array radius

Abstract

Abstract. A systematic study of annular aluminum-wire z-pinches on the Saturn accelerator shows that the quality of the implosion, (as measured by the radial convergence, the radiated energy, pulse width, and power), increases with wire number. Radiation magnetohydrodynamic (RMHC) xy simulations suggest that the implosion transitions from that of individual wire plasmas to that of a continuous plasma shell when the interwire spacing is reduced below -1.4 mm. In this "plasma-shell regime," many of the global radiation and plasma characteristics are in agreement with those simulated by 2D-FWHC rz simulations. In this regime, measured changes in the radiation pulse width with variations in load mass and array radius are consistent with the simulations and are explained by the development of 2D fluid motion in the rz plane. Associated variations in the K-shell yield are qualitatively explained by simple radiation-scaling models.

Numerical simulations of annular wire-array z-pinches in (x,y), (r,{theta}), and (r,z) geometries

“…His pulse width analysis, keeping the density perturbation fixed, is found to be in excellent agreement with our measured widths in the many-wire, plasma sheath regime [2]. For these TJ€' runs, a 10% random cell-to-cell density variation is imposed.…”

“…The Total Immersion PIC (TIP) code has been used in several geometries to understand better the measured dynamics of annular, aluminum wire-array z-pinches [ 1,2] on the Saturn [3] accelerator. The areas investigated include the formation of the plasma sheath from currentinduced individual wire explosions, the effects of wire number and symmetry on the implosion dynamics, and the dependence on wire number of the Rayleigh-Taylor (RT) instability growth.…”

Theoretical and numerical research of wire array Z-pinch and dynamic hohlraum at IAPCM

“…At the same time, MRT instability's effects on the Z-pinch stagnation and radiation were studied numerically, which has been found to provide good matches with experiments. Peterson [47,[51][52][53] has successfully shown agreement in radiation quantities and physical appearance using a random density seed for loads on four different experimental machines, Pegasus [47], Procyon [51], Saturn [52], and Z [53]. Hammer [54], and Douglas [55] have also successfully modeled Saturn experiments using a random density seed.…”