A Detailed Characterization of Power Flow and PRS Performance on Phoenix.
Abstract
This study first constructs a complete model of the Phoenix pulser and its puff gas load, connects the model with experimental findings, and then suggests some means of improving the pulser's K shell x-ray yield. A numerical study of energy coupling into a dummy resistive load showed that an output impedance of about 1 omega would minimize the reflected energy; from this result a thevenin equivalent circuit was constructed. Use of the transmission line model to study the Phoenix pre-pulse evolved to a study of early power flow and has produced a breakdown model that contains a detailed field map for the PRS load cavity, a mapping of the computed electric field values onto the grid of neutral gas density measurements, and a simple ionization model. Preliminary results from the breakdown model indicate ionization regions consistent with the observed 'reversed' zippering, and a Boltzmann solution in those regions shows that at 40% of peak field the ionization would proceed in about 6 ns. A series of full 1D MHD studies, equipped with both CRE and time dependent ionization and excited state models, has refined the expected yields for Ar gas to about 18 kJ using a 4 cm long, shell of 0.375 mgm mass.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 03, 1996
- Accession Number
- ADA309678
Entities
People
- J. L. Guiliani Jr.
- J. Rogerson
- Jack F. Davis
- K. G. Whitney
- R. E. Terry
Organizations
- United States Naval Research Laboratory