Mechanical Design of the ZR Magnetically Insulated Transmission Lines
Abstract not provided.
Publications
Analysis of the ZR vacuum insulator stack
Abstract not provided.
Magnetically driven isentropic compression to multi-mega-bar pressures using shaped current pulses on the Z accelerator
Physics of Plasmas (special issue)
Abstract not provided.
Magnetically driven isentropic compression to multi-megabar pressures using shaped current pulses on Z
Abstract not provided.
Shockless acceleration of flyer plates at multi-megabar magnetic pressures on the Z-machine
Abstract not provided.
Sheath-current retrapping in the Z MITLs
Digest of Technical Papers-IEEE International Pulsed Power Conference
An important issue in designing a higher-power version of the Z machine at Sandia National Laboratories is electron current loss in the vacuum section, which consists of four radial transmission lines and a convolute (current-adder). There is evidence from experiments on Z that 1-2MA of current out of about 20MA is lost in the vacuum section before reaching the wire-array load [1]. Calculations using the LSP [2] and QUICKSILVER [3] particle-in-cell codes have shown much less current loss [4,5,6]. The current loss in the calculations is due to sheath-current loss in the region of the convolute, and is associated with the magnetic nulls which are intrinsic to the current splitting in the convolute Detailed 2-D calculations for the radial MITLs show that, in the region between the insulator stack and a radius of about 20cm (over which the radial-line vacuum impedance increases slowly from 2Ω to 3Ω), excess electron sheath current is mostly retrapped to the cathode electrode. The electron sheath current is given approximately by Mendel's force-balance expression [7] applied locally, and as a result, the sheath current decreases as Zv-2, where Zv is the vacuum impedance. Between a radius of 20cm and the convolute, where the radial-line vacuum impedance increases more sharply (to 6Ω at 10cm) there is significant "launching" of sheath current. The sheath behavior in this region is qualitatively similar to that predicted using a "constant flow impedance" model, but in the simulations the sheath is unstable and breaks up into vortices.
A coupled 1-D transmission line and particle-in-cell model to simulate electron flow in the Z and ZR accelerators
Abstract not provided.
Pulse shaping of the load current on the Z accelerator
Abstract not provided.
Investigating the electromagnetic structure of the coax-to-triplate transition for the pulse-compression section of the ZR accelerator
Abstract not provided.
Results 76–84 of 84