Experiments and models of MHD jets and their relevance to astrophysics and solar physics

Abstract

Magnetohydrodynamic (MHD)-driven jets involve poloidal and toroidal magnetic fields, finite pressure gradients, and unbalanced forces. The mechanism driving these jets is first discussed qualitatively by decomposing the magnetic force into a curvature and a gradient component. The mechanism is then considered quantitatively by consideration of all terms in the three components of the MHD equation of motion and in addition, the implications of Ampere's law, Faraday's law, the ideal Ohm's law, and the equation of continuity. The analysis shows that jets are self-collimating with the tip of the jet moving more slowly than the main column of the jet so there is a continuous stagnation near the tip in the jet frame. Experiments supporting these conclusions are discussed and it is shown how this mechanism relates to jets in astrophysical and solar corona contexts.

Document Details

Document Type
Pub Defense Publication
Publication Date
Mar 12, 2018
Source ID
10.1063/1.5009571

Entities

People

  • Paul M. Bellan

Organizations

  • ARPA-E
  • Air Force Office of Scientific Research
  • California Institute of Technology
  • National Science Foundation

Tags

Fields of Study

  • Physics

Readers

  • Fluid Mechanics and Fluid Dynamics.
  • Plasma Physics / Magnetohydrodynamics
  • Plasma Physics.

Technology Areas

  • Space
  • Space - Hall-Effect Thruster