Application of 2-D simulations to hollow Z-pinch implosions

Abstract

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Wire array Z-pinch insights for enhanced x-ray production

“…Iineouts of the images in the r-z plane show that the wavelength of the RT structure is in the range of 1 to 3 mm, in agreement with RMHC simulations [15,24,40] and the Heuristic Model.…”

“…The data show that the narrow (<5 ns) radiation pulses generated by intecwire gaps below -0.5 mm can be realistically simulated by the 2-D Eulerian radiationmagnetohydrodynamic code (E-RMHC) [23,24], in which Rayleigh-Taylor (RT) growth dominates the implosion dynamics in the r-z plane. For these simulations, the array is idealized as a uniform, cylindrically-symmetric shell with a random-density variation in the r-z plane that seeds the RT instability.…”

“…The E-RMHC simulations give reasonable agreement with the total radiated power data over an order-of-magnitude variation in array mass and almost a factor of three change in load radius. The simulations suggest that in 2-D, the RT growth occurs via a two-staged process [24] which limits the RT development, and thus permits high x-ray power to be generated. The simulations also show the benefit to the generation of high radiation powers of using low-enough mass arrays and small-enough radius loads to minimize the growth of the RT instability balanced against the need for a high implosion velocity.…”

Computational investigation of the magneto-Rayleigh–Taylor instability in Z-pinch implosions

“…Peterson and co-workers [13][14][15][16] have successfully shown agreement in radiation quantities and physical appearance using a random density seed for loads on four different experimental machines, Pegasus, 13 Procyon, 14 Saturn, 15 and Z. 16 Roderick and co-workers, 7,13 Hammer et al, 17 and Douglas et al 18 have also successfully modeled Saturn experiments using a random density seed. These calculations showed that the MRT instability alone describes the majority of the pinch dynamics and that only a single variable ͑the initial perturbation amplitude͒ is necessary to accurately model the experimental data without resorting to modified or "anomalous" physical parameters.…”

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.…”