Electrical Conductivity Measurement of Nonideal Carbon Plasma

Abstract

Approved for public release; distribution is unlimited.ii REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704-0188Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing the burden, to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. REPORT DATE (DD-MM-YYYY) August 20082. REPORT TYPE PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) U.S. Army Research Laboratory ATTN: AMSRD-ARL-WM-TE Aberdeen Proving Ground, MD 21005-5069 PERFORMING ORGANIZATION REPORT NUMBER ARL-TR-4551 SPONSOR/MONITOR'S ACRONYM(S) 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) SPONSOR/MONITOR'S REPORT NUMBER(S) DISTRIBUTION/AVAILABILITY STATEMENTApproved for public release; distribution is unlimited. SUPPLEMENTARY NOTES* Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, MD 20742 ABSTRACTThe electrical conductivity of carbon plasmas is measured in the range of densities from 0.16 solid density down to about 0.05 solid density and reported for values of internal energy ranging from 4 to 22 kJ/g. Plasmas are formed by rapid electrical discharge through thin graphite fibers immersed in a water bath. The pressure in the expanding plasma column is determined by a hydrodynamic model to describe the effect on the water surround. At constant internal energy per unit mass U, conductivity σ varies with specific volume V as σ = V α , where α is about 1.2 for U 6 kJ/g < , and rises to about 1.5 for U = 22 kJ/g. SUBJECT TERMSplasma, electrical conductivity, carbon, energy, temperature

Experiments and Simulations of Exploding Aluminum Wires: Validation of ALEGRA-MHD

“…The experimental setup consisted of a cylindrical Al chamber 15-cm deep and 30-cm in diameter. Details of the experimental apparatus have been reported in our previous publications (14)(15)(16). In the previous experiments, we assumed the length of the wire to be equal to the plate separation.…”