2017 IEEE Pulsed Power Conference

Session

Oral session 11 - Plasma Z-Pinches, Pulsed X-ray Sources, High-Power Diodes, Wire Array Implosions - Session Chair : Michael Mazarakis

11

20 Jun 2017, 15:00

Hilton Brighton Metropole Hotel

337. Direct observation of electrothermal instability structures in the skin layer of an intensely Ohmically heated conductor

Dr Thomas Awe (Sandia National Laboratories)

20/06/2017, 15:00

High-Energy Density Physics and Technology

Oral

Magnetically driven implosions on the Z Facility assemble high-energy-density plasmas for radiation effects and ICF experiments. MDIs are hampered by the Magneto-Rayleigh-Taylor (MRT) instability, which can limit achievable stagnation pressures and temperatures. The metallic liners used in Magnetized Liner Inertial Fusion (MagLIF) experiments include astonishingly small (~10 nm RMS) initial...

77. Results of comparison between underwater explosions of Cu and Al wires and investigation of symmetry of a shock wave generated by a cylindrical wire array explosion

David Yanuka (Technion - Israel)

20/06/2017, 15:15

High-Energy Density Physics and Technology

Oral

Underwater electrical explosion of an Al wire can be accompanied by an exothermic process resulting in additional energy transferred to the generated water flow. Here, we report on recent results of a comparison between underwater electrical explosions of single Cu and Al wires. Experiments were carried out using a high-current pulse generator (70 kV, 40 kA, 100 ns). Using fast frame and...

80. Preconditioned wire array Z-pinch driven by a double-pulse current generator

Dr Jian Wu (Xi'an Jiaotong University)

20/06/2017, 15:30

High-Energy Density Physics and Technology

Oral

Recently, the concept of the preconditioned wire array Z-pinch was proposed in which the ablation phase was suppressed and the implosion involved all mass of the array. On MAGPIE facility, this was achieved for aluminum wire array by the employing a specially designed two stage wire array, which allowed the generation of a short prepulse current through the wires of the top imploding array,...

78. Generation of cylindrically convergent shockwaves in water on the MACH facility

Simon Bland (Imperial College London)

20/06/2017, 15:45

High-Energy Density Physics and Technology

Oral

We report on initial shock physics experiments performed on the MACH – Mega Ampere Compression and Hydrodynamics – facility at Imperial College London.

The MACH generator is a 2MA, 400ns, 100kV ‘dry air’ Linear Transformer Driver cavity, which can be readily expanded to higher currents and drive voltages. The generator was designed for ease of use, and rapid turnaround with a load region...

122. Recent progress in implosion of a quasi-spherical shock waves and x-ray imaging of exploding wires

Mikhail Nitishinskiy (Technion, Israel)

20/06/2017, 16:15

High-Energy Density Physics and Technology

Oral

Recent results on implosion of strong shock wave (SSW) generated by underwater electrical explosion of a spherical wire array are presented. Microsecond pulse generator (≤38 kV, ≤380 kA, rise time ~1.3 µs) was used for explosion of Cu and Al arrays with radii of 20mm, 25mm and 30mm. A strong light emission from water in the vicinity of the array origin was used to determine the SSW...

146. Cygnus Performance on Five Subcritical Experiments

Dr John Smith (Los Alamos National Laboratory)

20/06/2017, 16:30

High-Energy Density Physics and Technology

Oral

The Cygnus Dual Beam Radiographic Facility includes two identical radiographic sources - Cygnus 1 and Cygnus 2. Cygnus is the radiography source used in Subcritical Experiments (SCEs) at the Nevada National Security Site (NNSS). The machine specifications are: Electric - 2.25 MV, 60 kA, 60 ns; Radiation - 4 Rad, 1 mm, 50 ns; Operation - single shot, 2-shots/day. Cygnus has operated at the NNSS...

212. Magnetic-field evolution in Z-pinch implosion with preembedded axial magnetic field

Dmitry Mikitchuk (Weizmann Institute of Science)

20/06/2017, 16:45

High-Energy Density Physics and Technology

Oral

We investigate the effects of an axial magnetic field ($B_z$) on the current distribution in imploding plasma and the efficiency of the $B_z$-field compression by the imploding plasma. In the experiment, a cylindrical argon gas puff, in which is initially embedded quasi-static magnetic flux (up to 0.4 T), prefills the volume between two electrodes. Subsequently, a pulsed-current (rising to 300...

86. OVERVIEW OF THE EXPERIMENTAL DATA ON THE USE OF A VACUUM ARC DISCHARGE FOR Z-PINCHES

Dr Alexander Rousskikh (Institute of High Current Electronics)

20/06/2017, 17:00

High-Energy Density Physics and Technology

Oral

Development of the technology of using a vacuum arc discharge system for the formation of the metallic gas puff is going in two directions.
The first direction is the use of a plasma jet for the X-ray radiography. We have compared the spatial dimensions of the radiating hot spot based on the use of X-pinch and Point Z-pinch (PZ-pinch is a regular Z-pinch with a small initial size (diameter...

50. Experimental Platform Development for Studying Vacuum Power Flow Physics at the Sandia Z Accelerator

George Laity (Sandia National Laboratories)

20/06/2017, 17:15

High-Energy Density Physics and Technology

Oral

While the Z Facility can routinely deliver 25-27MA current pulses to a variety of high energy density physics experiments, load configurations which require high-inductance (>3.0 nH) hardware typically suffer from reduced current coupling in the form of charged particle losses in magnetically insulated transmission lines (MITLs). These losses: (1) can be difficult to model with conventional...