Instability heating of the HDZP [electronic resource].
- Washington, D.C. : United States. Dept. of Energy, 1993. and Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy.
- Physical Description:
- Pages: (10 pages) : digital, PDF file
- Additional Creators:
- Los Alamos National Laboratory, United States. Department of Energy, and United States. Department of Energy. Office of Scientific and Technical Information
- Restrictions on Access:
- Free-to-read Unrestricted online access
- We present a model of dense Z-Pinch heating. For pinches of sufficiently small diameter and high current, direct ion heating by m=0 instabilities becomes the principal channel for power input. This process is particularly important in the present generation of dense micro-pinches (e.g., HDZP-II) where instability growth times are much smaller than current risetimes, and a typical pinch diameter is several orders smaller than that of the chamber. Under these conditions, m=0 formation is not disruptive: the large E[sub z] field reconnects the instability cusps externally, after which the ingested magnetic flux decays into turbulent kinetic energy of the plasma. The continuous process is analogous to boiling of a heated fluid. A simple analysis shows that an equivalent resistance R[sub t] = [ell]/4[radical]Nm[sub i]([mu][sub 0]/[pi])[sup 3/2]I/r appears in the driving circuit, where I is the pinch current, N is the line density, [ell] is the pinch length, m[sub i] is the ion mass, and r is the pinch radius. A corresponding heating term has been added to the ion energy equation in a 0-D, self-similar simulation, which had been written previously to estimate fusion yields and radial expansion of D[sub 2] fiber pinches. The simulation results agree well with the experimental results from HDZP-II, where the assumption of only joule heating produced gross disagreement. Turbulent ion heating should be the dominant process in any simple pinch carrying meg-ampere current and having submillimeter radius.
- Published through SciTech Connect., 01/01/1993., "la-ur-93-1318", " conf-9304126--5", "DE93012641", 3. international conference on dense z-pinches, London (United Kingdom), 19-23 Apr 1993., and Riley, R.A.; Shlachter, J.S.; Lovberg, R.H.
- Funding Information:
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