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31. |
Flux‐trapping during the formation of field‐reversed configurations |
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Physics of Fluids(00319171),
Volume 25,
Issue 11,
1982,
Page 2121-2127
W. T. Armstrong,
D. G. Harding,
E. A. Crawford,
A. L. Hoffman,
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摘要:
Flux‐trapping during the early formation phases of a field‐reversed configuration has been studied experimentally on the field‐reversed theta‐pinch TRX‐1. An annularz‐pinch preionizer was employed to permit ionization at high values of reverse‐bias flux. Contrary to previous analysis, the rate of flux loss was not governed exclusively by inertially limited plasma convection to the tube walls. At high reverse flux levels, a pressure bearing sheath was observed to form at the tube walls and the flux loss was restricted by resistive diffusion across this sheath. The characteristic time for flux loss was 0.08rt(cm) &mgr;sec, independent of the bias field and independent of the fill pressure for fill pressures above 15 mTorr D2. Octopole barrier fields were found to be effective in limiting the inertially governed flux loss at very early times before the wall sheath formed.
ISSN:0031-9171
DOI:10.1063/1.863671
出版商:AIP
年代:1982
数据来源: AIP
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32. |
Internal heat deposition in laser highly accelerated targets |
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Physics of Fluids(00319171),
Volume 25,
Issue 11,
1982,
Page 2128-2131
B. H. Ripin,
E. A. McLean,
J. A. Stamper,
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PDF (302KB)
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摘要:
A novel method is described from which estimates of the internal pressure or temperature of highly accelerated material can be made. The technique utilizes the relationship of the initial free expansion properties of a fluid boundary to internal pressure. The technique is applied to Nd‐laser ablatively accelerated targets; the results compare well with target rear surface temperature measurements using time‐resolved optical pyrometry.
ISSN:0031-9171
DOI:10.1063/1.863672
出版商:AIP
年代:1982
数据来源: AIP
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