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The PHELIX Liner Demonstration Experiment (PLD-1) took place in September of 2010 at Los Alamos National Laboratory. The PHELIX machine consists of a 500 kJ single-marx capacitor bank cable-coupled to a toroidal 1:4 current step-up transformer which delivers multi-Mega- Ampere currents to a cm size load. In this experiment the load consisted of a 3 cm radius, 0.8 mm thick, 3 cm tall aluminum liner, copper glide planes, a thin polyethylene insulator, and a 0.5 cm thick aluminum return conductor. Two independent channels of fiber optic Faraday rotation measured a peak load current 4 MA with a pulse width of 10 s. Four linear Rogowski coils measured the output current of the 4 marx modules. High-resolution flash X-radiography imaged a stable, highly symmetric and uniform liner 14.5 s after current start. A 12 channel laser Doppler velocimetry (LDV) system tracked the inside surface of the liner throughout the experiment and showed a peak velocity before impact with probes of 1 km/s. The LDV probes were arrayed axially as well as azimuthally and confirmed the symmetry of the liner trajectory. Surprisingly, the LDV showed distribution of velocities of the inner liner surface late in time. PLD-1 is the first step towards utilizing the PHELIX pulsed-power system at the Los Alamos proton radiography facility., See also ADM002371. 2013 IEEE Pulsed Power Conference, Digest of Technical Papers 1976-2013, and Abstracts of the 2013 IEEE International Conference on Plasma Science. IEEE International Pulsed Power Conference (19th). Held in San Francisco, CA on 16-21 June 2013., The original document contains color images.

ALT-3 (Advanced Liner Technology) is a collaboration between VNIIEF and LANL that aims to conduct high velocity material experiments and measure shock velocities at pressures near 1 TPa. The DEMG (Disk Explosive Magnetic Generator) is used to drive a 60MA current that accelerates an aluminum liner to speeds in excess of 20 km/s. A simple circuit model is presented that models the DEMG to reasonable accuracy and is then coupled with 1-D magnetohydrodynamic simulations of both the liner and target. 2-D hydrodynamic simulations of the target are also presented along with implications for measurement accuracy and expected results., See also ADM002371. 2013 IEEE Pulsed Power Conference, Digest of Technical Papers 1976-2013, and Abstracts of the 2013 IEEE International Conference on Plasma Science. IEEE International Pulsed Power Conference (19th). Held in San Francisco, CA on 16-21 June 2013., The original document contains color images.

The PHELIX pulsed power project will introduce magnetically driven hydrodynamics experiments to the Los Alamos National Laboratory s proton radiography facility (pRad). The Precision High Energy-density Liner Implosion eXperiment (PHELIX) has been commissioned at Los Alamos. A small footprint capacitor bank consisting of four parallel connected single-stage marx units (500 kJ) is cable coupled to a toroidal, current stepup transformer to deliver multi-Mega-Ampere, 10 s current pulses to cm size cylindrical loads. In a sequence of tests the performance of each component (capacitor bank and transformer) was evaluated and compared to a circuit model. The transformer coupling was observed to be k 0.93. The tests culminated in a liner implosion experiment in which an 3 cm radius, 0.8 mm thick, 3 cm tall aluminum liner was accelerated to a velocity of 1 km/s. The suite of machine diagnostics included linear Rogowski coils and Faraday rotation for current measurements. The experimental diagnostics include Bdot probes, multi-channel photon Doppler velocimetry (PDV), and single-frame, flash X-radiography to evaluate the performance of the high precision liner implosion. Currently, work is focused on integrating PHELIX into normal operations with the 800 MeV proton radiography facilities. There, high-resolution, high-frame-rate imaging of hydrodynamic experiments will be possible., See also ADM002371. 2013 IEEE Pulsed Power Conference, Digest of Technical Papers 1976-2013, and Abstracts of the 2013 IEEE International Conference on Plasma Science. IEEE International Pulsed Power Conference (19th). Held in San Francisco, CA on 16-21 June 2013., The original document contains color images.

We use the Richtmyer-Meshkov instability (RMI) at a metal-gas interface to infer the metal’s yield stress (Y) under shock loading and release. We first model how Y stabilizes the RMI using hydrodynamics simulations with a perfectly plastic constitutive relation for copper (Cu). The model is then tested with molecular dynamics (MD) of crystalline Cu by comparing the inferred Y from RMI simulations with direct stress-strain calculations, both with MD at the same conditions. Finally, new RMI experiments with solid Cu validate our simulation-based model and infer Y~0.47 GPa for a 36 GPa shock.