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Title: Effect of insulator end cap thickness on time-dependent Hartmann flow in a rotating mirror

Journal Article · · Journal of Plasma Physics
ORCiD logo [1];  [2];  [3]; ORCiD logo [4]
  1. Princeton Univ., NJ (United States)
  2. Univ. of Maryland, College Park, MD (United States)
  3. Univ. of Wisconsin, Madison, WI (United States)
  4. Princeton Univ., NJ (United States); Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)

We present a framework for analysing plasma flow in a rotating mirror. By making a series of physical assumptions, we reduce the magnetohydrodynamic (MHD) equations in a three-dimensional cylindrical system to a one-dimensional system in a shallow, cuboidal channel within a transverse magnetic field, similar to the Hartmann flow in ducts. We then solve the system both numerically and analytically for a range of values of the Hartmann number and calculate the dependence of the plasma flow speed on the thickness of the insulating end cap. We observe that the mean flow overshoots and decelerates before achieving a steady-state value, a phenomenon that the analytical model cannot capture. This overshoot is directly proportional to the thickness of the insulating end cap and the external electric field, with a weak dependence on the external magnetic field. Our simplified model can act as a benchmark for future simulations of the supersonic mirror device CMFX (centrifugal magnetic fusion experiment), which will employ more sophisticated physics and realistic magnetic field geometries.

Research Organization:
Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
Sponsoring Organization:
USDOE
Grant/Contract Number:
AC02-09CH11466
OSTI ID:
2496684
Journal Information:
Journal of Plasma Physics, Journal Name: Journal of Plasma Physics Journal Issue: 6 Vol. 90; ISSN 0022-3778
Publisher:
Cambridge University PressCopyright Statement
Country of Publication:
United States
Language:
English

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